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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def register(cls, note, provider):
 """Implementation to register provider via `provider` & `factory`."""

        basenote, name = cls.parse_note(note)
        if 'provider_registry' not in vars(cls):
            cls.provider_registry = {}
        cls.provider_registry[basenote] = provider