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Python Introducing Lists Using Lists Mutability

Posted by Blair Walker
Blair Walker
12,672 Points

Doesn't the last example at the end of the video show that this actual "inventory" list is empty?

I tried to call back the list, but nothing is in there. And in the video, he calls "inventory" and its empty. Is this how it should be? Where did the list go?

1 Answer

Travis Alstrand
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Travis Alstrand
Treehouse Project Reviewer
Travis Alstrand
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Travis Alstrand
Treehouse Project Reviewer

Yes, he states at about 8:18 that he's looping over a copy but removing from the actual list. He's doing this because when looping over the actual list and trying to remove them, he hit the issues shown where two items still remained. So by looping over a copy, he's still able to access the same item variable, but he removes it from the actual list instead.

I hope that makes sense :smile:

You can read more on Shallow copies (what was seen here) and deep copies here