@utilities.arguments_not_none<EOL><INDENT>def unassign_composition_from_repository(self, composition_id, repository_id):<DEDENT>
<EOL>mgr = self._get_provider_manager('<STR_LIT>', local=True)<EOL>lookup_session = mgr.get_repository_lookup_session(proxy=self._proxy)<EOL>lookup_session.get_repository(repository_id)  <EOL>self._unassign_object_from_catalog(composition_id, repository_id)<EOL>
Removes ``Composition`` from a ``Repository``.

        arg:    composition_id (osid.id.Id): the ``Id`` of the
                ``Composition``
        arg:    repository_id (osid.id.Id): the ``Id`` of the
                ``Repository``
        raise:  NotFound - ``composition_id`` or ``repository_id`` not
                found or ``composition_id`` not assigned to
                ``repository_id``
        raise:  NullArgument - ``composition_id`` or ``repository_id``
                is ``null``
        raise:  OperationFailed - unable to complete request
        raise:  PermissionDenied - authorization failure
        *compliance: mandatory -- This method must be implemented.*