| ⇢ | A | env added | |
| ⇢ | A | 67d8fbce85bb_initial added |
| ⇢ | B | 67d8fbce85bb_initial.upgrade() added | |
| ⇢ | B | env.run_migrations_online() added | |
| ⇢ | A | env.get_metadata() added | |
| ⇢ | A | env.get_engine() added | |
| ⇢ | A | env.get_engine_url() added | |
| ⇢ | A | env.run_migrations_offline() added | |
| ⇢ | A | 67d8fbce85bb_initial.downgrade() added |