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Python Python Collections (2016, retired 2019) Lists Removing items from a list

Jonathan Kobylasnki
PLUS
Jonathan Kobylasnki
Courses Plus Student 2,343 Points

Task one no longer working?

No sure where i'm going wrong here I have done what the task ask's but now task one is no longer working?

lists.py
messy_list = ["a", 2, 3, 1, False, [1, 2, 3]]

# Your code goes below here
messy_list.insert(0, messy_list.pop(3))
messy_list.remove('a')
del messy_list[4]]
del messy_list[-1]

1 Answer

Stephan Livera
Stephan Livera
4,146 Points

Hi Jonathan,

I think what's happening here is the 'order of operations' is changing the list positions so you have to 'account for this' in your code. i.e. once you've "popped" the 1 back to index position 0, and removed "a" from the list, "False" is now in index position 3. Then once we delete "False" at index position 3, then the list [1, 2, 3] is NOW in index position 3 so we simply repeat the command to get rid of it.

Code below should work:

          # Your code goes below here
messy_list.insert(0, messy_list.pop(3))
messy_list.remove('a')
del messy_list[3]
del messy_list[3]

Stephan