code: def update_project(self, project_update, project_id):
          
          route_values = {}
          if project_id is not None:
              route_values['projectId'] = self._serialize.url('project_id', project_id, 'str')
          content = self._serialize.body(project_update, 'TeamProject')
          response = self._send(http_method='PATCH',
                                location_id='603fe2ac-9723-48b9-88ad-09305aa6c6e1',
                                version='5.1-preview.4',
                                route_values=route_values,
                                content=content)
          return self._deserialize('OperationReference', response)
docs: UpdateProject.
          [Preview API] Update an existing project's name, abbreviation, description, or restore a project.
          :param :class:`<TeamProject> <azure.devops.v5_1.core.models.TeamProject>` project_update: The updates for the project. The state must be set to wellFormed to restore the project.
          :param str project_id: The project id of the project to update.
          :rtype: :class:`<OperationReference> <azure.devops.v5_1.core.models.OperationReference>`