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

x is not defined

Not sure what I'm doing wrong. The error says x is not defined.

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(lst):
  total=0
  for x in (lst):
    total +=x
  return total

def summarize(lst):
  return "The sum of" + x + "is" + y

1 Answer

Hi peyton

in your summarize function your assigning a variable called x to the return string but you have not defined what x is. Try this

# 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(mylist):
  total=0
  for x in (mylist):
    total +=x
  return total

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