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Strange behavior with modifying list inside for loop in Python 3.11

👀 Views: 1286 đŸ’Ŧ Answers: 1 📅 Created: 2025-08-30
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I need help solving I keep running into I'm working with an scenario where I'm trying to modify a list while iterating through it with a for loop in Python 3.11... I expected the loop to iterate over the original list, but it seems to be skipping some elements. Here's a simplified version of the code I'm working with: ```python my_list = [1, 2, 3, 4, 5] for num in my_list: if num % 2 == 0: my_list.remove(num) print(f'Removed {num}') print(num) ``` When I run this code, I get the output: ``` Removed 2 1 3 4 5 ``` It looks like the loop skips the number `4`, which I don't understand. I thought the loop would continue through the original list, but it seems to be affected by the removal of elements. I've tried creating a copy of the list before iterating, but I'd like to understand the root cause of this behavior. Is modifying a list while iterating over it a bad practice? How can I effectively remove items from a list based on a condition without losing elements? Any insights would be appreciated! Am I missing something obvious? I'm using Python 3.9 in this project. I'm open to any suggestions.