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Python Python Basics (Retired) Putting the "Fun" Back in "Function" Functions

Make a function named add_list that takes a list.The function should then add all of the items in the list together

Make a function named add_list that takes a list.The function should then add all of the items in the list together and return the total. Assume the list contains only numbers. You’ll probably want to use a for loop. You will not need to use input().

functions.py
lists = []

def add_list(num):
  return (num+)
Matthew Turner
Matthew Turner
2,564 Points

you need to make a function with an iterable parameter. And you need to get the sum of all the items in the iterable.

Try this:

def add_list(iterable): sum = 0 for i in iterable: sum += i return sum

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,064 Points

You need to loop through the input list and sum each item:

def add_list(lst):
    # Init Total
    total = 0
    for item in list:
        total += item #<-- same as total = total + item
    return (total)

You could also cheat a bit by using a function you've not yet learned about: sum()

def add_list(lst):
    return sum(lst)