for testing and deploying your application
for finding and fixing issues
for empowering human code reviews
from collections import Counter
def checkio(data):
for i in [x for x, y in Counter(data).items() if y == 1]:
data.remove(i)
return data
# for self-testing
if __name__ == "__main__": # pragma: no cover
assert checkio([1, 2, 3, 1, 3]) == [1, 3, 1, 3], "1st example"
assert checkio([1, 2, 3, 4, 5]) == [], "2nd example"
assert checkio([5, 5, 5, 5, 5]) == [5, 5, 5, 5, 5], "3rd example"
assert checkio([10, 9, 10, 10, 9, 8]) == [10, 9, 10, 10, 9], "4th example"