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Silvie Cinkova
1,742 Pointsexplicit help with Code Challenge Manipulation of Lists, please
Please give me the full solution to this exercise. I have tried a for-loop, but Python changes the variable on the fly, which messes up the indices. So I tried a bypass by renaming all non-numbers, but this does not work either. I have tried for several hours and need to move on. Please give me the expected solution. Thank you.
for i in the_list: try: float(i) except TypeError or ValueError: i = "remove"
the_list.remove("remove")
2 Answers
Chris Freeman
Treehouse Moderator 68,423 PointsThe challenge can be solved using:
# Task 1 of 3
# Move the 1 to position 0. You can do this in one step with
# .pop() and .insert().
the_list = ["a", 2, 3, 1, False, [1, 2, 3]]
# pop the '1' (item at index three) and insert at position 0
the_list.insert(0, the_list.pop(3))
# Task 2 of 3
# Use '.remove()' and/or 'del' to remove the string, boolean,
# and list members of the_list.
the_list.remove("a")
the_list.remove(False)
the_list.remove([1, 2, 3])
# Task 3 of 3
# Now, make the_list contain only the numbers 1 through 20
# by using '.extend()'.
the_list.extend(range(4, 21))
Silvie Cinkova
1,742 PointsAaaah.... fair enough :-) I assumed the code should work more generally, and got in trouble detecting the type of each list member in a loop. If this is the accepted solution, then the task is really easy. So I have not missed anything important from the lessons. Thanks!
Jordan Bester
4,752 PointsJordan Bester
4,752 Pointshey how is task 3 correct i'm not quite understanding the range function??
What I dont understand is how or why is 4,21 being used to represent the range of numbers between 1 and 20?
Chris Freeman
Treehouse Moderator 68,423 PointsChris Freeman
Treehouse Moderator 68,423 PointsRange(start, stop) goes from start to stop, including the start, and upto but not including the stop. So range(4, 21) produces 4 through 20.