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Python Object-Oriented Python (retired) Objects Create a Class with a Method

Ahmed Elsawey
Ahmed Elsawey
Courses Plus Student 3,527 Points

What is wrong with the last line or formatting the string?

Why s my formatting wrong? chris freeman

class Store:
  open = 9
  close = 10
  def hours(self):
    return ("We're open from {} to {}.".format(open, close))

1 Answer

Chris Freeman
Chris Freeman
Treehouse Moderator 68,167 Points

I suspect the error message is 'close' is not defined. The question is then, for your "close", where is it defined?

"close" is looked for in the following places:

  • a local variable to hours(): Nope!
  • a parameter to `hours()': Nope!
  • a instance attribute: Nope! (you'll learn more about these later)
  • a class attribute: BINGO! open and close are class attributes that can be reference using self.open and self.close.

Add self. to your format parameters: ...format(self.open, self.close)

BTW, the reason that open wasn't flagged as "not defined" is because open() is a built-in function which I suspect is not what you want to pass to your format() string. It's a HORRIBLE name to use as a coding example. IMHO