code: def configure_flask(graph):
      
      app = Flask(graph.metadata.import_name)
      app.debug = graph.metadata.debug
      app.testing = graph.metadata.testing
  
      # copy in the graph's configuration for non-nested keys
      app.config.update({
          key: value
          for key, value in graph.config.items()
          if not isinstance(value, dict)
      })
  
      return app
docs: Create the Flask instance (only), bound to the "flask" key.
  
      Conventions should refer to `graph.flask` to avoid circular dependencies.