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Python Python Basics (2015) Shopping List App Refactor

Alexandra Montgomery
Alexandra Montgomery
520 Points

I'm doing this right but its not working

I don't know what is wrong here. I've been trying to pass this exercise for days

def show_help():
    # print out instructions on how to use the app
    print("What should we pick up at the store?")
Enter 'DONE' to stop adding items.
Enter 'HELP' for this help.
Enter 'SHOW' to see your current list.

def show_list(shopping_list):
    # print out the list
    print("Here's your list:")

    for item in shopping_list:

def add_to_list(shopping_list, new_item):
    # add new items to our list
    print("Added {}. List now has {} items.".format(new_item, len(shopping_list)))
    return shopping_list

def main():

# make a list to hold onto our items
    shopping_list = []

while True:
    # ask for new items
    new_item = input("> ")

    # be able to quit the app
    if new_item == 'DONE':
    elif new_item == 'HELP':
    elif new_item == 'SHOW':
    add_to_list(shopping_list, new_item)


2 Answers

Hi Alexandra,

I believe the issue is here:

def main():

# make a list to hold onto our items
    shopping_list = []

Because of Python's semantically relevant whitespacing/indentation, this formatting makes the interpreter think that the shopping_list variable is part of the main() function. That renders it inaccessible (due to scope) outside of that functiion.

Just backspace the variable to the beginning of the line and see if that doesn't fix things.

Best, Cena

Afrid Mondal
Afrid Mondal
6,255 Points

Hey Alexandra Montgomery, actually the problem is indentation. just indent your shopping_list and while and shopping_list(at last line). it will work fine.