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Python Python Collections (Retired) Lists Redux Manipulating Lists

Posted by Shahar Polak
Shahar Polak
5,756 Points

This code works but I can't submit the answer...

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

# Your code goes below here
first = the_list.pop(3)
the_list.insert(0,first)

temp_list = []

for item in the_list:
  if type(item) == int:
    if item > 0 and item <20:
      temp_list.append(item)

the_list.extend(temp_list)

1 Answer

Iain Simmons
MOD
Iain Simmons
Treehouse Moderator 32,305 Points
Iain Simmons
Iain Simmons
Treehouse Moderator 32,305 Points

First up, you don't have the code used for the second task to remove the string ("a"), boolean (False) or the nested list ([1, 2, 3]). Add that first, and then the_list would contain [1, 2, 3].

Second, you're only looping through the existing list and adding to the temp_list. You need another list containing the numbers up until 20 that don't already exist in the_list (i.e. 4 through 20).

Since you're 'extending' the list, you don't need to loop through what is already in there, you just need to somehow add what is missing.

Have a look at using range().

Shahar Polak
Shahar Polak
5,756 Points

Great thanks, I've done it a bit differently using a helper variable list .