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Jacob Keeley2,033 Points
Why isn't .remove() deleting lists?
When I try to complete Task 2 of Removing Items from a List using the code below, Python outputs
[1, 2, 3, [1, 2, 3]]. Why does the list within the list remain?
messy_list = ["a", 2, 3, 1, False, [1, 2, 3]] messy_list.insert(0, messy_list.pop(3)) for item in messy_list: if type(item) != int: messy_list.remove(item) else: continue
Steven Parker221,291 Points
This issue occurs when an iterable is altered while being used to control a loop. Disturbing the item order can cause items to be skipped over.
To prevent this, use a copy of the iterable for the loop (using the "copy" method or a slice with no arguments).