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Python Python Basics (2015) Shopping List App Refactor

Alex Durham
PLUS
Alex Durham
Courses Plus Student 456 Points

indent

Are these lines not indented properly?

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 ():  # <-- space before paren throwing off checker.
    show_help()
# make a list to hold onto our items
    shopping_list = []
    while True:
    # ask for new items
        new_item = input("> ")  # <-- incorrect indentation in while loop
    # be able to quit the app
        if new_item == 'DONE':  # <-- incorrect indentation in while loop
            break
        elif new_item == 'HELP':  # <-- incorrect indentation in while loop
            show_help()
            continue 
        elif new_item == 'SHOW':  # <-- incorrect indentation in while loop
            show_list(shopping_list)
            continue
        add_to_list(shopping_list, new_item)  # <-- incorrect indentation in while loop
        show_list(shopping_list)

2 Answers

Jeff Wilton
Jeff Wilton
16,646 Points

This is one of those slightly frustrating cases where it is not looking for proper Python syntax, but instead it is looking for something formatted EXACTLY the way they expect. Just adding a single comment, extra space or # character makes the challenge fail. You did have the last line wrongly indented, but even that doesn't fix the problem until I removed all of your comments and inserted line breaks where they expected them to be.

def main():
    show_help()

    # 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':
            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)
Steven Parker
Steven Parker
229,771 Points

Only the first comment must be removed.

I also found it necessary to remove the space as Kenneth Love had suggested in a previous answer, so the comment did not make sense any more anyway. But (to Kenneth) — shouldn't the challenge ignore the comment?

So after fixing that, and the bad indentation on the last line, this passed the challenge:

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()
# make a list to hold onto our items
    shopping_list = []
    while True:
    # ask for new items
        new_item = input("> ")  # <-- incorrect indentation in while loop
    # be able to quit the app
        if new_item == 'DONE':  # <-- incorrect indentation in while loop
            break
        elif new_item == 'HELP':  # <-- incorrect indentation in while loop
            show_help()
            continue 
        elif new_item == 'SHOW':  # <-- incorrect indentation in while loop
            show_list(shopping_list)
            continue
        add_to_list(shopping_list, new_item)  # <-- incorrect indentation in while loop
    show_list(shopping_list)
Kenneth Love
Kenneth Love
Treehouse Guest Teacher

Updated. The comments shouldn't matter.

Steven Parker
Steven Parker
229,771 Points

Thanks for the rapid service!