| 1 |  |  | # | 
            
                                                                                                            
                            
            
                                    
            
            
                | 2 |  |  | # Copyright 2014 Quantopian, Inc. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 3 |  |  | # | 
            
                                                                                                            
                            
            
                                    
            
            
                | 4 |  |  | # Licensed under the Apache License, Version 2.0 (the "License"); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 5 |  |  | # you may not use this file except in compliance with the License. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 6 |  |  | # You may obtain a copy of the License at | 
            
                                                                                                            
                            
            
                                    
            
            
                | 7 |  |  | # | 
            
                                                                                                            
                            
            
                                    
            
            
                | 8 |  |  | #     http://www.apache.org/licenses/LICENSE-2.0 | 
            
                                                                                                            
                            
            
                                    
            
            
                | 9 |  |  | # | 
            
                                                                                                            
                            
            
                                    
            
            
                | 10 |  |  | # Unless required by applicable law or agreed to in writing, software | 
            
                                                                                                            
                            
            
                                    
            
            
                | 11 |  |  | # distributed under the License is distributed on an "AS IS" BASIS, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 12 |  |  | # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 13 |  |  | # See the License for the specific language governing permissions and | 
            
                                                                                                            
                            
            
                                    
            
            
                | 14 |  |  | # limitations under the License. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 15 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 16 |  |  | """ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 17 |  |  | Position Tracking | 
            
                                                                                                            
                            
            
                                    
            
            
                | 18 |  |  | ================= | 
            
                                                                                                            
                            
            
                                    
            
            
                | 19 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 20 |  |  |     +-----------------+----------------------------------------------------+ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 21 |  |  |     | key             | value                                              | | 
            
                                                                                                            
                            
            
                                    
            
            
                | 22 |  |  |     +=================+====================================================+ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 23 |  |  |     | sid             | the sid for the asset held in this position        | | 
            
                                                                                                            
                            
            
                                    
            
            
                | 24 |  |  |     +-----------------+----------------------------------------------------+ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 25 |  |  |     | amount          | whole number of shares in the position             | | 
            
                                                                                                            
                            
            
                                    
            
            
                | 26 |  |  |     +-----------------+----------------------------------------------------+ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 27 |  |  |     | last_sale_price | price at last sale of the asset on the exchange    | | 
            
                                                                                                            
                            
            
                                    
            
            
                | 28 |  |  |     +-----------------+----------------------------------------------------+ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 29 |  |  |     | cost_basis      | the volume weighted average price paid per share   | | 
            
                                                                                                            
                            
            
                                    
            
            
                | 30 |  |  |     +-----------------+----------------------------------------------------+ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 31 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 32 |  |  | """ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 33 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 34 |  |  | from __future__ import division | 
            
                                                                                                            
                            
            
                                    
            
            
                | 35 |  |  | from math import ( | 
            
                                                                                                            
                            
            
                                    
            
            
                | 36 |  |  |     copysign, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 37 |  |  |     floor, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 38 |  |  | ) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 39 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 40 |  |  | from copy import copy | 
            
                                                                                                            
                            
            
                                    
            
            
                | 41 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 42 |  |  | import logbook | 
            
                                                                                                            
                            
            
                                    
            
            
                | 43 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 44 |  |  | from zipline.utils.serialization_utils import ( | 
            
                                                                                                            
                            
            
                                    
            
            
                | 45 |  |  |     VERSION_LABEL | 
            
                                                                                                            
                            
            
                                    
            
            
                | 46 |  |  | ) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 47 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 48 |  |  | log = logbook.Logger('Performance') | 
            
                                                                                                            
                            
            
                                    
            
            
                | 49 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 50 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 51 |  |  | class Position(object): | 
            
                                                                                                            
                            
            
                                    
            
            
                | 52 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 53 |  |  |     def __init__(self, sid, amount=0, cost_basis=0.0, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 54 |  |  |                  last_sale_price=0.0, last_sale_date=None): | 
            
                                                                                                            
                            
            
                                    
            
            
                | 55 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 56 |  |  |         self.sid = sid | 
            
                                                                                                            
                            
            
                                    
            
            
                | 57 |  |  |         self.amount = amount | 
            
                                                                                                            
                            
            
                                    
            
            
                | 58 |  |  |         self.cost_basis = cost_basis  # per share | 
            
                                                                                                            
                            
            
                                    
            
            
                | 59 |  |  |         self.last_sale_price = last_sale_price | 
            
                                                                                                            
                            
            
                                    
            
            
                | 60 |  |  |         self.last_sale_date = last_sale_date | 
            
                                                                                                            
                                                                
            
                                    
            
            
                | 61 |  |  |  | 
            
                                                                        
                            
            
                                    
            
            
                | 62 |  |  |     def earn_dividend(self, dividend): | 
            
                                                                        
                            
            
                                    
            
            
                | 63 |  |  |         """ | 
            
                                                                        
                            
            
                                    
            
            
                | 64 |  |  |         Register the number of shares we held at this dividend's ex date so | 
            
                                                                        
                            
            
                                    
            
            
                | 65 |  |  |         that we can pay out the correct amount on the dividend's pay date. | 
            
                                                                        
                            
            
                                    
            
            
                | 66 |  |  |         """ | 
            
                                                                        
                            
            
                                    
            
            
                | 67 |  |  |         out = {} | 
            
                                                                        
                            
            
                                    
            
            
                | 68 |  |  |  | 
            
                                                                        
                            
            
                                    
            
            
                | 69 |  |  |         out['amount'] = self.amount * dividend.amount | 
            
                                                                        
                            
            
                                    
            
            
                | 70 |  |  |         return out | 
            
                                                                                                            
                            
            
                                    
            
            
                | 71 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 72 |  |  |     def earn_stock_dividend(self, stock_dividend): | 
            
                                                                                                            
                            
            
                                    
            
            
                | 73 |  |  |         """ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 74 |  |  |         Register the number of shares we held at this dividend's ex date so | 
            
                                                                                                            
                            
            
                                    
            
            
                | 75 |  |  |         that we can pay out the correct amount on the dividend's pay date. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 76 |  |  |         """ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 77 |  |  |         out = {} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 78 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 79 |  |  |         # stock dividend | 
            
                                                                                                            
                            
            
                                    
            
            
                | 80 |  |  |         out['payment_sid'] = stock_dividend.payment_sid | 
            
                                                                                                            
                            
            
                                    
            
            
                | 81 |  |  |         out['share_count'] = floor( | 
            
                                                                                                            
                            
            
                                    
            
            
                | 82 |  |  |             self.amount * float(stock_dividend.ratio)) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 83 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 84 |  |  |         return out | 
            
                                                                                                            
                            
            
                                    
            
            
                | 85 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 86 |  |  |     def handle_split(self, sid, ratio): | 
            
                                                                                                            
                            
            
                                    
            
            
                | 87 |  |  |         """ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 88 |  |  |         Update the position by the split ratio, and return the resulting | 
            
                                                                                                            
                            
            
                                    
            
            
                | 89 |  |  |         fractional share that will be converted into cash. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 90 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 91 |  |  |         Returns the unused cash. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 92 |  |  |         """ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 93 |  |  |         if self.sid != sid: | 
            
                                                                                                            
                            
            
                                    
            
            
                | 94 |  |  |             raise Exception("updating split with the wrong sid!") | 
            
                                                                                                            
                            
            
                                    
            
            
                | 95 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 96 |  |  |         log.info("handling split for sid = " + str(sid) + | 
            
                                                                                                            
                            
            
                                    
            
            
                | 97 |  |  |                  ", ratio = " + str(ratio)) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 98 |  |  |         log.info("before split: " + str(self)) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 99 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 100 |  |  |         # adjust the # of shares by the ratio | 
            
                                                                                                            
                            
            
                                    
            
            
                | 101 |  |  |         # (if we had 100 shares, and the ratio is 3, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 102 |  |  |         #  we now have 33 shares) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 103 |  |  |         # (old_share_count / ratio = new_share_count) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 104 |  |  |         # (old_price * ratio = new_price) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 105 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 106 |  |  |         # e.g., 33.333 | 
            
                                                                                                            
                            
            
                                    
            
            
                | 107 |  |  |         raw_share_count = self.amount / float(ratio) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 108 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 109 |  |  |         # e.g., 33 | 
            
                                                                                                            
                            
            
                                    
            
            
                | 110 |  |  |         full_share_count = floor(raw_share_count) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 111 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 112 |  |  |         # e.g., 0.333 | 
            
                                                                                                            
                            
            
                                    
            
            
                | 113 |  |  |         fractional_share_count = raw_share_count - full_share_count | 
            
                                                                                                            
                            
            
                                    
            
            
                | 114 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 115 |  |  |         # adjust the cost basis to the nearest cent, e.g., 60.0 | 
            
                                                                                                            
                            
            
                                    
            
            
                | 116 |  |  |         new_cost_basis = round(self.cost_basis * ratio, 2) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 117 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 118 |  |  |         self.cost_basis = new_cost_basis | 
            
                                                                                                            
                            
            
                                    
            
            
                | 119 |  |  |         self.amount = full_share_count | 
            
                                                                                                            
                            
            
                                    
            
            
                | 120 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 121 |  |  |         return_cash = round(float(fractional_share_count * new_cost_basis), 2) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 122 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 123 |  |  |         log.info("after split: " + str(self)) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 124 |  |  |         log.info("returning cash: " + str(return_cash)) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 125 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 126 |  |  |         # return the leftover cash, which will be converted into cash | 
            
                                                                                                            
                            
            
                                    
            
            
                | 127 |  |  |         # (rounded to the nearest cent) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 128 |  |  |         return return_cash | 
            
                                                                                                            
                            
            
                                    
            
            
                | 129 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 130 |  |  |     def update(self, txn): | 
            
                                                                                                            
                            
            
                                    
            
            
                | 131 |  |  |         if self.sid != txn.sid: | 
            
                                                                                                            
                            
            
                                    
            
            
                | 132 |  |  |             raise Exception('updating position with txn for a ' | 
            
                                                                                                            
                            
            
                                    
            
            
                | 133 |  |  |                             'different sid') | 
            
                                                                                                            
                            
            
                                    
            
            
                | 134 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 135 |  |  |         total_shares = self.amount + txn.amount | 
            
                                                                                                            
                            
            
                                    
            
            
                | 136 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 137 |  |  |         if total_shares == 0: | 
            
                                                                                                            
                            
            
                                    
            
            
                | 138 |  |  |             self.cost_basis = 0.0 | 
            
                                                                                                            
                            
            
                                    
            
            
                | 139 |  |  |         else: | 
            
                                                                                                            
                            
            
                                    
            
            
                | 140 |  |  |             prev_direction = copysign(1, self.amount) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 141 |  |  |             txn_direction = copysign(1, txn.amount) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 142 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 143 |  |  |             if prev_direction != txn_direction: | 
            
                                                                                                            
                            
            
                                    
            
            
                | 144 |  |  |                 # we're covering a short or closing a position | 
            
                                                                                                            
                            
            
                                    
            
            
                | 145 |  |  |                 if abs(txn.amount) > abs(self.amount): | 
            
                                                                                                            
                            
            
                                    
            
            
                | 146 |  |  |                     # we've closed the position and gone short | 
            
                                                                                                            
                            
            
                                    
            
            
                | 147 |  |  |                     # or covered the short position and gone long | 
            
                                                                                                            
                            
            
                                    
            
            
                | 148 |  |  |                     self.cost_basis = txn.price | 
            
                                                                                                            
                            
            
                                    
            
            
                | 149 |  |  |             else: | 
            
                                                                                                            
                            
            
                                    
            
            
                | 150 |  |  |                 prev_cost = self.cost_basis * self.amount | 
            
                                                                                                            
                            
            
                                    
            
            
                | 151 |  |  |                 txn_cost = txn.amount * txn.price | 
            
                                                                                                            
                            
            
                                    
            
            
                | 152 |  |  |                 total_cost = prev_cost + txn_cost | 
            
                                                                                                            
                            
            
                                    
            
            
                | 153 |  |  |                 self.cost_basis = total_cost / total_shares | 
            
                                                                                                            
                            
            
                                    
            
            
                | 154 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 155 |  |  |             # Update the last sale price if txn is | 
            
                                                                                                            
                            
            
                                    
            
            
                | 156 |  |  |             # best data we have so far | 
            
                                                                                                            
                            
            
                                    
            
            
                | 157 |  |  |             if self.last_sale_date is None or txn.dt > self.last_sale_date: | 
            
                                                                                                            
                            
            
                                    
            
            
                | 158 |  |  |                 self.last_sale_price = txn.price | 
            
                                                                                                            
                            
            
                                    
            
            
                | 159 |  |  |                 self.last_sale_date = txn.dt | 
            
                                                                                                            
                            
            
                                    
            
            
                | 160 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 161 |  |  |         self.amount = total_shares | 
            
                                                                                                            
                            
            
                                    
            
            
                | 162 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 163 |  |  |     def adjust_commission_cost_basis(self, sid, cost): | 
            
                                                                                                            
                            
            
                                    
            
            
                | 164 |  |  |         """ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 165 |  |  |         A note about cost-basis in zipline: all positions are considered | 
            
                                                                                                            
                            
            
                                    
            
            
                | 166 |  |  |         to share a cost basis, even if they were executed in different | 
            
                                                                                                            
                            
            
                                    
            
            
                | 167 |  |  |         transactions with different commission costs, different prices, etc. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 168 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 169 |  |  |         Due to limitations about how zipline handles positions, zipline will | 
            
                                                                                                            
                            
            
                                    
            
            
                | 170 |  |  |         currently spread an externally-delivered commission charge across | 
            
                                                                                                            
                            
            
                                    
            
            
                | 171 |  |  |         all shares in a position. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 172 |  |  |         """ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 173 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 174 |  |  |         if sid != self.sid: | 
            
                                                                                                            
                            
            
                                    
            
            
                | 175 |  |  |             raise Exception('Updating a commission for a different sid?') | 
            
                                                                                                            
                            
            
                                    
            
            
                | 176 |  |  |         if cost == 0.0: | 
            
                                                                                                            
                            
            
                                    
            
            
                | 177 |  |  |             return | 
            
                                                                                                            
                            
            
                                    
            
            
                | 178 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 179 |  |  |         # If we no longer hold this position, there is no cost basis to | 
            
                                                                                                            
                            
            
                                    
            
            
                | 180 |  |  |         # adjust. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 181 |  |  |         if self.amount == 0: | 
            
                                                                                                            
                            
            
                                    
            
            
                | 182 |  |  |             return | 
            
                                                                                                            
                            
            
                                    
            
            
                | 183 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 184 |  |  |         prev_cost = self.cost_basis * self.amount | 
            
                                                                                                            
                            
            
                                    
            
            
                | 185 |  |  |         new_cost = prev_cost + cost | 
            
                                                                                                            
                            
            
                                    
            
            
                | 186 |  |  |         self.cost_basis = new_cost / self.amount | 
            
                                                                                                            
                            
            
                                    
            
            
                | 187 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 188 |  |  |     def __repr__(self): | 
            
                                                                                                            
                            
            
                                    
            
            
                | 189 |  |  |         template = "sid: {sid}, amount: {amount}, cost_basis: {cost_basis}, \ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 190 |  |  | last_sale_price: {last_sale_price}" | 
            
                                                                                                            
                            
            
                                    
            
            
                | 191 |  |  |         return template.format( | 
            
                                                                                                            
                            
            
                                    
            
            
                | 192 |  |  |             sid=self.sid, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 193 |  |  |             amount=self.amount, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 194 |  |  |             cost_basis=self.cost_basis, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 195 |  |  |             last_sale_price=self.last_sale_price | 
            
                                                                                                            
                            
            
                                    
            
            
                | 196 |  |  |         ) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 197 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 198 |  |  |     def to_dict(self): | 
            
                                                                                                            
                            
            
                                    
            
            
                | 199 |  |  |         """ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 200 |  |  |         Creates a dictionary representing the state of this position. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 201 |  |  |         Returns a dict object of the form: | 
            
                                                                                                            
                            
            
                                    
            
            
                | 202 |  |  |         """ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 203 |  |  |         return { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 204 |  |  |             'sid': self.sid, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 205 |  |  |             'amount': self.amount, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 206 |  |  |             'cost_basis': self.cost_basis, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 207 |  |  |             'last_sale_price': self.last_sale_price | 
            
                                                                                                            
                            
            
                                    
            
            
                | 208 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 209 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 210 |  |  |     def __getstate__(self): | 
            
                                                                                                            
                            
            
                                    
            
            
                | 211 |  |  |         state_dict = copy(self.__dict__) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 212 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 213 |  |  |         STATE_VERSION = 1 | 
            
                                                                                                            
                            
            
                                    
            
            
                | 214 |  |  |         state_dict[VERSION_LABEL] = STATE_VERSION | 
            
                                                                                                            
                            
            
                                    
            
            
                | 215 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 216 |  |  |         return state_dict | 
            
                                                                                                            
                            
            
                                    
            
            
                | 217 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 218 |  |  |     def __setstate__(self, state): | 
            
                                                                                                            
                            
            
                                    
            
            
                | 219 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 220 |  |  |         OLDEST_SUPPORTED_STATE = 1 | 
            
                                                                                                            
                            
            
                                    
            
            
                | 221 |  |  |         version = state.pop(VERSION_LABEL) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 222 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 223 |  |  |         if version < OLDEST_SUPPORTED_STATE: | 
            
                                                                                                            
                            
            
                                    
            
            
                | 224 |  |  |             raise BaseException("Position saved state is too old.") | 
            
                                                                                                            
                            
            
                                    
            
            
                | 225 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 226 |  |  |         self.__dict__.update(state) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 227 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 228 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 229 |  |  | class positiondict(dict): | 
            
                                                                                                            
                            
            
                                    
            
            
                | 230 |  |  |     def __missing__(self, key): | 
            
                                                                                                            
                                                                
            
                                    
            
            
                | 231 |  |  |         return None | 
            
                                                        
            
                                    
            
            
                | 232 |  |  |  |