code: def _get_lt_from_user_by_id(self, user, lt_id):
          
          req = meta.Session.query(LayerTemplate).select_from(join(LayerTemplate, User))
          try:
              return req.filter(and_(User.login==user, LayerTemplate.id==lt_id)).one()
          except Exception, e:
              return None
docs: Get a layertemplate owned by a user from the database by lt_id.