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Python Python Basics (2015) Shopping List App Refactor

Posted by Lalitha Venkataramani
Lalitha Venkataramani
509 Points

This challenge to add main function isnt' working. It says try again. Looks to be simple..but not sure what is not right

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("> ")

# 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)

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()

# 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)

3 Answers

Christof Baumgartner
Christof Baumgartner
20,864 Points
Christof Baumgartner
Christof Baumgartner
20,864 Points

You nearly had it. You added def main() at the correct spot, but missed the colons and the indentation afterwards, so the correct code would look like this:

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("> ")

        # 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)
Lalitha Venkataramani
Lalitha Venkataramani
509 Points
Lalitha Venkataramani
Lalitha Venkataramani
509 Points

I pasted your code from the one below and now it works...not sure what was the issue with my code. Looked the same

Lalitha Venkataramani
Lalitha Venkataramani
509 Points
Lalitha Venkataramani
Lalitha Venkataramani
509 Points

Thnx for catching that mistake....but still it doesn't work