(cls, backend_type, phone_number, domain=None)
return None
Chooses the appropriate backend based on the phone number's
        prefix, or returns None if no catch-all backend is configured.

        backend_type - SQLMobileBackend.SMS or SQLMobileBackend.IVR
        phone_number - the phone number
        domain - pass in a domain to choose the default backend from the domain's
                 configured backends, otherwise leave None to choose from the
                 system's configured backends
Chooses the appropriate backend based on the phone number's
        prefix, or returns None if no catch-all backend is configured.
Chooses the appropriate backend based on the phone number s prefix or returns None if no catch - all backend is configured .
def load_default_backend(cls, backend_type, phone_number, domain=None):
        """
        Chooses the appropriate backend based on the phone number's
        prefix, or returns None if no catch-all backend is configured.

        backend_type - SQLMobileBackend.SMS or SQLMobileBackend.IVR
        phone_number - the phone number
        domain - pass in a domain to choose the default backend from the domain's
                 configured backends, otherwise leave None to choose from the
                 system's configured backends
        """
        backend_map = SQLMobileBackendMapping.get_prefix_to_backend_map(
            backend_type, domain=domain)
        backend_id = backend_map.get_backend_id_by_prefix(phone_number)
        if backend_id:
            return cls.load(backend_id)
        return None
def load_default_backend ( cls , backend_type , phone_number , domain = None ) : backend_map = SQLMobileBackendMapping . get_prefix_to_backend_map ( backend_type , domain = domain ) backend_id = backend_map . get_backend_id_by_prefix ( phone_number ) if backend_id : return cls . load ( backend_id ) return None