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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 __get_activator_method(self, method_name):
 """ Retrieves the requested method of the activator, or returns None :param method_name: A method name :return: A method, or None """

        # Get the activator
        activator = getattr(self.__module, ACTIVATOR, None)
        if activator is None:
            # Get the old activator
            activator = getattr(self.__module, ACTIVATOR_LEGACY, None)
            if activator is not None:
                # Old activator found: print a deprecation warning
                _logger.warning(
                    "Bundle %s uses the deprecated '%s' to declare"
                    " its activator. Use @BundleActivator instead.",
                    self.__name,
                    ACTIVATOR_LEGACY,
                )
        return getattr(activator, method_name, None)