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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def is_parent(self, id_, parent_id):
 """Tests if an ``Id`` is a direct parent of another. arg: id (osid.id.Id):
 the ``Id`` to query arg: parent_id (osid.id.Id):
 the ``Id`` of a parent return: (boolean) - ``true`` if this ``parent_id`` is a parent of ``id,`` ``false`` otherwise raise: NotFound - ``id`` is not found raise: NullArgument - ``id`` or ``parent_id`` is ``null`` raise: OperationFailed - unable to complete request raise: PermissionDenied - authorization failure *compliance: mandatory -- This method must be implemented.* *implementation notes*: If ``parent_id`` not found return ``false``. """

        return bool(self._rls.get_relationships_by_genus_type_for_peers(
            parent_id,
            id_,
            self._relationship_type).available())