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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 __check_deprecated(self):
 """ Checks for deprecated configuration keys """

        # Depracation notices
        if "SANIC_JWT_HANDLER_PAYLOAD_SCOPES" in self.app.config:
            raise exceptions.InvalidConfiguration(
                "SANIC_JWT_HANDLER_PAYLOAD_SCOPES has been deprecated. "
                "Instead, pass your handler method (not an import path) as "
                "initialize(add_scopes_to_payload=my_scope_extender)"
            )

        if "SANIC_JWT_PAYLOAD_HANDLER" in self.app.config:
            raise exceptions.InvalidConfiguration(
                "SANIC_JWT_PAYLOAD_HANDLER has been deprecated. "
                "Instead, you will need to subclass Authentication. "
            )

        if "SANIC_JWT_HANDLER_PAYLOAD_EXTEND" in self.app.config:
            raise exceptions.InvalidConfiguration(
                "SANIC_JWT_HANDLER_PAYLOAD_EXTEND has been deprecated. "
                "Instead, you will need to subclass Authentication. "
                "Check out the documentation for more information."
            )