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![dthomas4](https://uploads.teamtreehouse.com/production/profile-photos/11651238/micro_Capture.jpg)
dthomas4
2,984 PointsWhy does 'add_to_list' function take an argument of 'item' but 'show_list' doesn't?
Both functions are using item, one is adding the item to the list, the other is printing the item. They both need item, so why isn't item passed to 'show_list'
2 Answers
![Jonathan Grieve](https://uploads.teamtreehouse.com/production/profile-photos/601842/micro_twitterCover.png)
Jonathan Grieve
Treehouse Moderator 91,253 PointsIt's hard to say too much without the code you're trying, but it sounds like you're asking about variables passed to function arguments.
Just glancing at the video I think what's happening is show_list():
is using list object that is in the global scope so that is the variable it is using. And the data that is appended and used in another function. In show list, item
` is a tracking variable that displays each value as it is looped over.
Remember that variables passed as parameters to a function are placeholders for information passed in a function call.
![Evan Dix](https://uploads.teamtreehouse.com/production/profile-photos/11695787/micro_tree.webp)
Evan Dix
1,597 PointsAs Johnathan pointed out, Craig is showing the list by iterating through a global variable -- meaning it can be seen and used by other functions and code within a program. So as you are adding tiems to the global list, you are continuously building it up so that it can be used later.
I actually did it a bit different, but it still acheives the same result. I think my solution is a not as efficient as it uses more code to acheive the same thing, which I think it typically frowned upon with programming. But I hope this helps you understand.
Here is my solution:
def show_list(list):
for item in list.copy():
print("* {}".format(item))
show_list(shopping_list)