code: def start_update(self):
          
          target_url = self._client.get_url('LAYER', 'POST', 'update', {'layer_id': self.id})
          r = self._client.request('POST', target_url, json={})
          return self._manager.create_from_result(r.json())
docs: A shortcut to create a new version and start importing it.
          Effectively the same as :py:meth:`.create_draft_version` followed by :py:meth:`koordinates.layers.Layer.start_import`.
  
          :rtype: Layer
          :return: the new version
          :raises Conflict: if there is already a draft version for this layer.