docs: def get_composition_admin_session_for_repository(self, repository_id, proxy):
          """Gets a composiiton administrative session for the given repository.
  
          arg:    repository_id (osid.id.Id): the ``Id`` of the repository
          arg:    proxy (osid.proxy.Proxy): a proxy
          return: (osid.repository.CompositionAdminSession) - a
                  ``CompositionAdminSession``
          raise:  NotFound - ``repository_id`` not found
          raise:  NullArgument - ``repository_id`` or ``proxy`` is
                  ``null``
          raise:  OperationFailed - unable to complete request
          raise:  Unimplemented - ``supports_composition_admin()`` or
                  ``supports_visible_federation()`` is ``false``
          *compliance: optional -- This method must be implemented if
          ``supports_composition_admin()`` and
          ``supports_visible_federation()`` are ``true``.*
  
          """
          if not self.supports_composition_admin():
              raise errors.Unimplemented()
          ##
          # Also include check to see if the catalog Id is found otherwise raise errors.NotFound
          ##
          # pylint: disable=no-member
          return sessions.CompositionAdminSession(repository_id, proxy, self._runtime)