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

Posted by Bach Vu
Bach Vu
8,293 Points

def summarize(list_num): sum = add_list(list_num) print("The sum of {} is {}.".format(list_num, sum))

Why I got this code wrong? I tested and it really worked but the challenge task gave me the bummer.

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(list_num):
  total = 0
  for num in list_num:
    total += num
  return total

def summarize(list_num):
  sum = add_list(list_num)
  print("The sum of {} is {}.".format(list_num, sum))

2 Answers

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

task 2 states: Now, make a function named summarize that also takes a list. It should return the string "The sum of X is Y.", replacing "X" with the string version of the list and "Y" with the sum total of the list.

you need to return the string, not print it:

# 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(list_num):
  total = 0
  for num in list_num:
    total += num
  return total

def summarize(list_num):
  sum = add_list(list_num)
  return "The sum of {} is {}.".format(list_num, sum)
Bill Talkington
Bill Talkington
11,840 Points
Bill Talkington
Bill Talkington
11,840 Points

I had the same issue; kept trying to print it. Thanks!

Ron Fisher
Ron Fisher
5,752 Points
Ron Fisher
Ron Fisher
5,752 Points

I believe the output to the screen is correct and what they are looking for. However, in the background you have something else going on. Try this in the python shell:

type(list_num)

type(str(list_num))

You will see that one is a of the Class 'list' and one of the Class 'str'. I believe the challenge was to make sure you output to the screen the string representation not the list itself.

I hope this helps.