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

isam elbousserghini
isam elbousserghini
1,959 Points

how do you add the items in the list?

how do you add items to the list?

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

2 Answers

akak
akak
29,445 Points

Hi Isam,

I don't have access to the challenge right now so I can't check if that's exactly what you are asked for, but this solution is more or less what you are looking for.

list = [1, 2, 3]

def add_list(list):
    total = 0
    for item in list:
        total += item
    return total

def summarize(list):
    total = 0
    for item in list:
        total += item
    return "The sum of {} is {}.".format(list, total)
Chris Freeman
Chris Freeman
Treehouse Moderator 68,033 Points

It's best not to use reserved words, such as list, as variable or arguments names. Common alternative is "lst".

using total = 0 brought up an error saying the total equaled 1, so i changed the 0 to a 5 and got it back as correct. however, i'm honestly not sure why that is, also i don't know what the "+=" does

akak
akak
29,445 Points

total += item is a shorter way of writing total = total + item.

total = total + item 
total += item #does exactly the same as the previous one

The idea here is that you add each number to total.

total = 0, add 1 
total = 1, add 2
total = 3, add 3
total = 6 

I don't know why it doesn't work for you. Maybe the challenge wants to do it different way. Can't check that since my account is paused at the moment. Sorry.

Chris Freeman
Chris Freeman
Treehouse Moderator 68,033 Points

total += item

is shorthand for

total = total + item

"so i changed the 0 to a 5" does not seem correct. Can you repost your code?

i went back and changed it back to 0 and it worked fine, not sure why i had to make it a 5 the first time.