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

Cheri Watts
Cheri Watts
658 Points

walk me through this challenge pls. i am completely lost and frustrated.

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().

# 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.

1 Answer

29,445 Points

Hi Cheri,

def add_list(list):  #define a function that takes a list
  result = 0       #create a variable that will hold the result
  for number in list:   # loop through each number in the list 
     result += number   #add each number to the result
  return result    #return the result

It could be also simplified to:

def add_list(list):
  return sum(list)


Cheri Watts
Cheri Watts
658 Points


I thank you so much for your assistance with this problem. Sadly, I have no earthly idea what you are talking about. I am very slow at computers to put the cards on the table. I am not here picking up a language on top of the three other languages I already know. I am lost at sea in the middle of the ocean trying to swim back to shore and getting very discouraged.

Thank you once again.