code: def set_project(self, project):
          
          def visit(x):
              # Try to set_project, then recurse through any values()
              set_project = getattr(x, 'set_project', None)
              if set_project:
                  set_project(project)
              values = getattr(x, 'values', lambda: ())
              for v in values():
                  visit(v)
  
          visit(self.routing)
docs: Set the base project for routing.