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John Smith
Python Web Development Techdegree Student 1,052 PointsWhat's the simplest way to solve this using insert and pop method?
Please help!
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(str("a"))
messy_list.remove(False)
2 Answers
Grigorij Schleifer
10,365 PointsHi Ruddy, I think you use the simplest way to solve this challenge already 
messy_list.remove("a")
messy_list.remove(False)
messy_list.remove([1, 2, 3])
Another way would be to use a for loop that checks the type of every list item and removes it if it is not an integer. The code could look like this:
# use [:] to create a copy of the list to be able to modify and iterate simultaneously
# otherwise you will delete an item and mess with up the iteration
# use type method, because otherwise you will compare a reference to a item and not item itself
for item in messy_list[:]:
if type(item) != int:
messy_list.remove(item)
Does it make sense?
John Smith
Python Web Development Techdegree Student 1,052 PointsIt does make sense, what doesn't make sense is that it keeps returning >>>"You need to move the 1 to the front of the list."
The challenge is:
Alright, my list is messy! Help me clean it up!
First, start by moving the 1 from index 3 to index 0. Try to do this in a single step by using both .pop() and .insert(). It's OK if it takes you more than one step, though!
Grigorij Schleifer
10,365 PointsHey, I think the challenge interpreter is going kind of insane. I had the same error message. I solved it by reloading the page. And be careful. You don´t need the str() method in the first remove statement. And don't forget to remove the list.
John Smith
Python Web Development Techdegree Student 1,052 PointsThank you Grigorij, I found the answer on this link.
https://teamtreehouse.com/community/syntaxerror-for-letter-in-messylist
It was much more simple than what it seems.
Jay Reyes
Python Web Development Techdegree Student 15,937 PointsI was looking for this. I was trying to use messy_list.copy() instead of messy_list[:] BUT we haven't learned about slices yet ;)
John Smith
Python Web Development Techdegree Student 1,052 PointsThat's odd, for some reason I still cannot get it to work even after refreshing the page multiple times. Does anyone have any idea why this doesn't work? Maybe the interpreter is looking for a specific way of coding this problem.
John Smith
Python Web Development Techdegree Student 1,052 PointsThis post helped out, I finally found the answer. It was a lot more straight forward than I thought.
https://teamtreehouse.com/community/syntaxerror-for-letter-in-messylist
Thanks for helping Grigorij!
John Smith
Python Web Development Techdegree Student 1,052 PointsJohn Smith
Python Web Development Techdegree Student 1,052 PointsIt keep saying I can't just simply add the 1, but I have to move the one to the front of the list.
typo *messy_list.insert(0, 1)