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

Alex Espinosa
Alex Espinosa
3,226 Points
Posted by Alex Espinosa
Alex Espinosa
3,226 Points

Join Syntax

---Python def summarize(list): total = add_list(list)

return "The sum of {} is {}".format(''.join(list), total)

I run into problems with this code and believe it relates to the join method. I was thinking potentially that the error I could be receiving is because total is an int, which is being passed into a string but this doesn't seem to be the problem

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):
  total = 0
  for num in list:
    total += num
  return total

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

1 Answer

Iain Simmons
MOD
Iain Simmons
Treehouse Moderator 32,305 Points
Iain Simmons
Iain Simmons
Treehouse Moderator 32,305 Points

Yeah join concatenates a list of strings together, but you only have integers.

In this case, you don't need the joins, because the desired output representation of the list is the default (square brackets, comma separated).

See here:

>>> [1,2,3].__str__()
'[1, 2, 3]'
>>> [1,2,3].__repr__()
'[1, 2, 3]'
>>> str([1,2,3])
'[1, 2, 3]'

So just past the list itself to format.