def get_bundle_imported_services(self, bundle):
        """
        Returns this bundle's ServiceReference list for all services it is
        using or returns None if this bundle is not using any services.
        A bundle is considered to be using a service if its use count for that
        service is greater than zero.

        The list is valid at the time of the call to this method, however, as
        the Framework is a very dynamic environment, services can be modified
        or unregistered at any time.

        :param bundle: The bundle to look into
        :return: The references of the services used by this bundle
        """
        with self.__svc_lock:
            return sorted(self.__bundle_imports.get(bundle, []))
Returns this bundle's ServiceReference list for all services it is
        using or returns None if this bundle is not using any services.
        A bundle is considered to be using a service if its use count for that
        service is greater than zero.

        The list is valid at the time of the call to this method, however, as
        the Framework is a very dynamic environment, services can be modified
        or unregistered at any time.

        :param bundle: The bundle to look into
        :return: The references of the services used by this bundle