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

Christian Green
Christian Green
603 Points

Functions and Lists

This is the problem: "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()."

So I make a function using "def add_list" and then put the list inside of the "add_list" with a colon, so it looks like: "def add_list([]):". I keep getting syntax error, it's the first step and and I need help, PLEASE!

functions.py
def add_list([]):
# 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

Dan Johnson
Dan Johnson
40,532 Points

What [] will do is create a new empty list. What you're looking to do when defining a function is to name the arguments that you'll need passed in so you can reference the data:

def add_list(numbers):

With that signature you could use numbers to refer to the list that was passed in.