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

Format of function

def addlist(new_item):

Why we have written new_item next to addlist What if we didn't write that.

1 Answer

Since this is the definition of the function, you can choose how many arguments the function should accept. If you remove the new_item variable from the definition, then your function will not take any variables as input.

In order to use new_item inside of the addlist function, it must be in those parentheses ( ). If you remove it from the definition, but try to use the function, you will receive an error.

def addlist():
  print(new_item)

new_item = 'apples'
addlist(new_item)

The code above results in an error message: TypeError: addlist() takes 0 positional arguments but 1 was given