docs: function execute(item, next) {
        if ('function' !== typeof item.fn) item.fn = model[item.fn];
        return item.fn.call(model, model.get(item.value), function (error, value) {
          if (error) return next(error);
  
          //
          // Only store the value if it is returned directly from the hook.
          //
          if (value) model.set(item.value, value);
          next();
        });
      }