• 2, 4 bug?

 

I am not sure if this is a bug or not, but here is my code:

for item in data: if(data.count(item) == 1): data.remove(item); else: continue

It works on every assertion except for Assertion #2 ([1, 2, 3, 4, 5]) which returns, ([2, 4]). Is this a bug, or is my code off?

From: http://www.checkio.org/mission/non-unique-elements/solve/

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