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

Posted by Tristan Gaebler
Tristan Gaebler
6,204 Points

Could someone point me in the right direction...

I'm an task 1/2. I can make a function, but forgot how to ass lists. Could someone nudge me in the right direction.

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([]):

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,441 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points
  1. Add together list items using built-in function
result = sum( list )

2.Loop over items and add them to subtotal:

result = 0
for item in list:
    result += item

You will also need to have an argument in your function: def add_list(arg):

Combining all of this, you would have something like this:

def add_list(arg):
    result = sum(arg)
    return result

or combining the last two statements:

def add_list(arg):
    return sum(arg)
Tristan Gaebler
Tristan Gaebler
6,204 Points

It's not really working. I don't think I fully get what your saying.

Tristan Gaebler
Tristan Gaebler
6,204 Points

That really helped, thanks! Could you take a look at the second challenge. Here's my code. What arguments do I pass to .format

''

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(arg): return sum(arg)

def summarize(arg2): return "The sum of {} is {}".format

Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points

The first argument would be the arg2. The second argument would be the sum which can be written as add_list(arg2). Putting those together you get:

def summarize(arg2):
    return "The sum of {} is {}".format(arg2, add_list(arg2))
Tristan Gaebler
Tristan Gaebler
6,204 Points

Thanks for the help!!!!!!!