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Python Python Basics (2015) Shopping List App Second Shopping List App

Jiwon Kim
Jiwon Kim
999 Points
Posted by Jiwon Kim
Jiwon Kim
999 Points

Shopping_list_2.py 1. SHOW does not show my current list. 2. print(.... format(new_item, len( ))) not working

  1. SHOW does not show my current list.
  2. print(.... format(new_item, len( ))) not working
  3. DONE does not recall the completed list.

This is a link (https://w.trhou.se/wggf4lwjjb)

shopping_list = []

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():
  #print out the list
  print("Here is your list:")
  for item in shopping_list:
      print(item)

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

show_help()

#while loop to run forever 
#ask for new items 
#be able to quit the app
while True:
  new_item = input("> ")
  if new_item == 'DONE':
    break
  elif new_item == 'HELP':
    show_help()
    continue
  elif new_item == 'SHOW':
    show_list()
    continue
          ```

2 Answers

Andreas cormack
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Andreas cormack
Python Web Development Techdegree Graduate 33,011 Points
Andreas cormack
.a{fill-rule:evenodd;}techdegree seal-36
Andreas cormack
Python Web Development Techdegree Graduate 33,011 Points

Hi Jiwon

The reason its not working is because you are not actually adding anything to the shopping_list. You have created an add_to_list function but you dont seem to be calling it.

shopping_list = []

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():
  #print out the list
  print("Here is your list:")
  for item in shopping_list:
      print(item)

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

show_help()

#while loop to run forever 
#ask for new items 
#be able to quit the app
while True:
  new_item = input("> ")
  if new_item == 'DONE':
    break
  elif new_item == 'HELP':
    show_help()
    continue
  elif new_item == 'SHOW':
    show_list()
    continue
  # added this else statement. If any of the above conditions are not met, it means user wants to add to the list 
  else:
    add_to_list(new_item)
    continue
Wu Ray
Wu Ray
2,359 Points
Wu Ray
Wu Ray
2,359 Points

I see you have created adding_list function but seems you never put it into your while loop which means you did't call it. Like Andrea had mentioned you have to put it into your loop so python know you want to add it.