code: def value_get(method_name):
      
  
      def value_get(value, context, **_params):
          method = getattr(value, method_name)
          return _get(method, context["key"], (), {})
  
      return value_get
docs: Creates a getter that will call value's method with specified name
      using the context's key as first argument.
      @param method_name: the name of a method belonging to the value.
      @type method_name: str