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Python Python Basics (2015) Shopping List App Refactor

Posted by Brian Jemison
Brian Jemison
3,832 Points

Issue with shopping_list_2.py challenge task 1

I keep getting the challenge task wrong and I am having a bit of a struggle determining what exactly is wrong as the error message only says "Try again". The challenge is: This challenge is a little different. You shouldn't have to write very much code. You probably recognize this code. It's pretty much our shopping_list_2.py from before. I want you to help me with a little refactor, though. Refactoring is when we change code to make it better, often by creating new functions. Create a new function named main that doesn't take any arguments. Move everything from line 22 (show_help()) and below into your new function. You shouldn't have any code that isn't inside of a function.

shopping_list.py 
def show_help():
    # print out instructions on how to use the app
    print("What should we pick up at the store?")
    print("""
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:
        print(item)

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

def main():
    show_help()    

    shopping_list = []

    while True:
        new_item = input("> ")


    if new_item == 'DONE':
        break
    elif new_item == 'HELP':
        show_help()
        continue
    elif new_item == 'SHOW':
        show_list(shopping_list)
        continue
    add_to_list(shopping_list, new_item)
    show_list(shopping_list)

2 Answers

Ted Dunn
Ted Dunn
43,783 Points

The problem is with the indentation of your code (this matters in Python). The lines beginning with if new_item == 'DONE' through (and including) add_to_list(shopping_list, new_item) all need to be indented one more level/one more tab.

def main():
    show_help()    

    shopping_list = []

    while True:
        new_item = input("> ")


        if new_item == 'DONE':
            break
        elif new_item == 'HELP':
            show_help()
            continue
        elif new_item == 'SHOW':
            show_list(shopping_list)
            continue
        add_to_list(shopping_list, new_item)
    show_list(shopping_list)
Brian Jemison
Brian Jemison
3,832 Points

Thank you so much! I was thinking that something was wrong regarding the syntax of the code. It didn't even occur to me that there was a problem with my indentation. Thanks again!

Camray Austin
PLUS
Camray Austin
Courses Plus Student 725 Points
Camray Austin
Camray Austin
Courses Plus Student 725 Points

Why isn't def main(): being called at the end of the function?