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

huyen nguyen
huyen nguyen
850 Points
Posted by huyen nguyen
huyen nguyen
850 Points

why it does not work :(

please help!!!

lists.py 
messy_list = ["a", 2, 3, 1, False, [1, 2, 3]]
x=messy_list.pop(3)
y=messy_list.insert(0,x)
for i in messy_list:
    if i is not int:
        return messy_list.remove(i)


# Your code goes below here

1 Answer

Andrew Mlamba
Andrew Mlamba
15,642 Points
Andrew Mlamba
Andrew Mlamba
15,642 Points

Through some research i got this from the Python documentation. Here is the link to the docs. List Comprehensions

In so many words, we are told to build a new list based on the old one.

This was my solution.

messy_list = ["a", 2, 3, 1, False, [1, 2, 3]]

# Your code goes below here

a = messy_list.pop(3)
b = messy_list.insert(0, a)

# build a new list based on the old one:
messy_list = [item for item in messy_list if type(item) == int]

Hope this helps.

PS:Is there anyone who managed Challenge Task 1 of 2 in one step?

William Li
William Li
Courses Plus Student 26,868 Points
William Li
William Li
Courses Plus Student 26,868 Points

actually the assignment to variable b is not needed. As to your question, here's one-liner for part 1

messy_list.insert(0, messy_list.pop(3))