code: def update_classification_node(self, posted_node, project, structure_group, path=None):
          
          route_values = {}
          if project is not None:
              route_values['project'] = self._serialize.url('project', project, 'str')
          if structure_group is not None:
              route_values['structureGroup'] = self._serialize.url('structure_group', structure_group, 'TreeStructureGroup')
          if path is not None:
              route_values['path'] = self._serialize.url('path', path, 'str')
          content = self._serialize.body(posted_node, 'WorkItemClassificationNode')
          response = self._send(http_method='PATCH',
                                location_id='5a172953-1b41-49d3-840a-33f79c3ce89f',
                                version='5.0',
                                route_values=route_values,
                                content=content)
          return self._deserialize('WorkItemClassificationNode', response)
docs: UpdateClassificationNode.
          Update an existing classification node.
          :param :class:`<WorkItemClassificationNode> <azure.devops.v5_0.work_item_tracking.models.WorkItemClassificationNode>` posted_node: Node to create or update.
          :param str project: Project ID or project name
          :param TreeStructureGroup structure_group: Structure group of the classification node, area or iteration.
          :param str path: Path of the classification node.
          :rtype: :class:`<WorkItemClassificationNode> <azure.devops.v5_0.work_item_tracking.models.WorkItemClassificationNode>`