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Python Python Collections (2016, retired 2019) Slices Back and Forth

Posted by Joe Mackey
Joe Mackey
20,418 Points

Alright, let's make this last step a bit harder and do two things. Make a copy of favorite_things

I made a copy of favorite_things favorite_things=sorted_things[:].sort()

slices.py 
favorite_things = ['raindrops on roses', 'whiskers on kittens', 'bright copper kettles',
                   'warm woolen mittens', 'bright paper packages tied up with string',
                   'cream colored ponies', 'crisp apple strudels']
slice1 = favorite_things[1:4]
slice2 = favorite_things[-2:]
favorite_things=sorted_things[:].sort() # added line 6 and Task 1 is no longer passing ??? 
                                        # make a copy of favorite_things and call it sorted_things then sort. Tried with and without the [:]
                                        # I am missing something here, any reading suggestions?

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,441 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points

Since the list method .sort() operates on a list in-place a copy needs to be made before it can be sorted. The line:

favorite_things=sorted_things[:].sort()

is trying to make a copy of sorted_things which has not yet been defined. The correct approach is using two steps:

  • define sorted_things as a slice copy of favorite_things
  • run the sort method directly using sorted_things.sort()

Post back if you need more help. Good Luck!!