code: def update_node(self, node_id, version, node_spec=None):
          
          url = self._url('/nodes/{0}/update?version={1}', node_id, str(version))
          res = self._post_json(url, data=node_spec)
          self._raise_for_status(res)
          return True
docs: Update the node's configuration
  
          Args:
  
              node_id (string): ID of the node to be updated.
              version (int): The version number of the node object being
                  updated. This is required to avoid conflicting writes.
              node_spec (dict): Configuration settings to update. Any values
                  not provided will be removed. Default: ``None``
  
          Returns:
              `True` if the request went through.
  
          Raises:
              :py:class:`docker.errors.APIError`
                  If the server returns an error.
  
          Example:
  
              >>> node_spec = {'Availability': 'active',
                           'Name': 'node-name',
                           'Role': 'manager',
                           'Labels': {'foo': 'bar'}
                          }
              >>> client.update_node(node_id='24ifsmvkjbyhk', version=8,
                  node_spec=node_spec)