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

Function Error

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().

I can't understand what wrong with my code:

def add_list([1,2,3])
   for item in add_list:
       print (item+item+item)

[MOD: added ```python markdown formattting -cf]

Chris Freeman
Chris Freeman
Treehouse Moderator 68,166 Points

Sorry, your code didn't post to the forum. Can you please add it to your post?

Now can you see it ?

1 Answer

Chris Freeman
Chris Freeman
Treehouse Moderator 68,166 Points

There are 6 issues with your code:

def add_list(a_list):  # <--#1 missing colon at end of line. #2 provide parameter instead of hardcoded value
    total = 0  # <-- need to initiate total before loop
    for item in a_list:  # <-- operate on parameter instead of function name
        total = total + item # <-- need to accumulate total as for loop runs
    return total  # <-- need a return statement to send value back. A print is not sufficient