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

Posted by Ryan Lail
Ryan Lail
4,386 Points

My code for challenge 2 won't pass. Why?

So I don't really understand why my code won't pass or how to make it pass. Please help.

~Ryan

functions.py 
# add_list([1, 2, 3]) should return 6
# summarize([1, 2, 3]) should return "The sum of [1, 2, 3] is 6."
# Note: both functions will only take *one* argument each.
def add_list (list1):
  total = 0
  for i in list1:
    total = total + i
  return total

def summarize (list1):
  return "The sum of {} is {}.".format(list1,total)

2 Answers

Hayley Swimelar
Hayley Swimelar
7,124 Points

You're almost there!

Your second function can't "see" the total value from your first value. Any variable that you declare inside of a function is only used inside that function and nowhere else.

So in your section function you should make another total variable that's equal to the total of the list you've passed to it. You can use the first you've written function to do this, like this:

def summarize (list1):
  total = add_list(list1)
  return "The sum of {} is {}.".format(list1,total)

Calling functions from within other functions is a very common programming technique and it's a great way to make your code more organized and easier to read.

Ryan Lail
Ryan Lail
4,386 Points

Thanks Hayley, I can't believe I forgot that I could just call the function inside my second function! Also thanks for such a quick reply.

Ratik Sharma
Ratik Sharma
32,885 Points
Ratik Sharma
Ratik Sharma
32,885 Points

In your code, the total variable is a part of the add_list function and is not accessible inside summarize. The way you have to do this is to call add_list from summarise and pass it an argument. Hope this helps!