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chevano gordon
3,399 Pointsneed help cant figure out how to add the three parameters at once
i know that reversing the list by every three numbers should be like list_name[::-3] since list_name[::-1] reverse the list by one item each time
messy_list = [5, 2, 1, 3, 4, 7, 8, 0, 9, -1]
# Your code goes below here
clean_list = messy_list[:]
clean_list.sort()
3 Answers
Chris Freeman
Treehouse Moderator 68,423 PointsYou have the correct answer (be sure to be slicing messy_list on Task 3):
# lists.py
messy_list = [5, 2, 1, 3, 4, 7, 8, 0, 9, -1]
# Task 1 of 3
# Copy messy_list using slice syntax into a new variable clean_list.
clean_list = messy_list[:]
# Task 2 of 3
# Sort clean_list using the sort() method.
clean_list.sort()
# Task 3 of 3
# Now, create a variable named silly_list that is every third item, backwards, from messy_list. For example, the first two items in silly_list should be [-1, 8].
silly_list = messy_list[::-3]
Wendy Turner
718 PointsWhy can't you do silly_list = messy_list[9:0:-3]
Chris Freeman
Treehouse Moderator 68,423 PointsGiven the three indexes, start, stop, and step, the stop must be larger than the start or there will be no list to step through:
>>> messy_list[9:0]
[]
>>> messy_list[9:9]
[]
Lisa Burbon
1,030 Pointssilly_list = messy_list[-1::-3]
chevano gordon
3,399 Pointschevano gordon
3,399 PointsHi Chris Freeman,
I did just that and it never worked, let me try again.