docs: def get_relationship_search_session_for_family(self, family_id=None, proxy=None):
          """Gets the ``OsidSession`` associated with the relationship search service for the given family.
  
          arg:    family_id (osid.id.Id): the ``Id`` of the family
          arg:    proxy (osid.proxy.Proxy): a proxy
          return: (osid.relationship.RelationshipSearchSession) - a
                  ``RelationshipSearchSession``
          raise:  NotFound - no ``Family`` found by the given ``Id``
          raise:  NullArgument - ``family_id`` or ``proxy`` is ``null``
          raise:  OperationFailed - unable to complete request
          raise:  Unimplemented - ``supports_relationship_search()`` or
                  ``supports_visible_federation()`` is ``false``
          *compliance: optional -- This method must be implemented if ``supports_relationship_search()``
              and ``supports_visible_federation()`` are ``true``*
  
          """
          if not family_id:
              raise NullArgument
          if not self.supports_relationship_search():
              raise Unimplemented()
          ##
          # Need to include check to see if the familyId is found otherwise raise NotFound
          ##
          try:
              from . import sessions
          except ImportError:
              raise OperationFailed()
          proxy = self._convert_proxy(proxy)
          try:
              session = sessions.RelationshipSearchSession(family_id, proxy=proxy, runtime=self._runtime)
          except AttributeError:
              raise OperationFailed()
          return session