docs: def get_resource_agent_session(self):
          """Gets the session for retrieving resource agent mappings.
  
          return: (osid.resource.ResourceAgentSession) - a
                  ``ResourceAgentSession``
          raise:  OperationFailed - unable to complete request
          raise:  Unimplemented - ``supports_resource_agent()`` is
                  ``false``
          *compliance: optional -- This method must be implemented if
          ``supports_resource_agent()`` is ``true``.*
  
          """
          if not self.supports_resource_agent():
              raise errors.Unimplemented()
          # pylint: disable=no-member
          return sessions.ResourceAgentSession(runtime=self._runtime)