code: function(object, map) {
        Object.keys(map).forEach(function(name) {
          var method = map[name];
          if (name in object) return;
          if (supportsDescriptors) {
            Object.defineProperty(object, name, {
              configurable: true,
              enumerable: false,
              writable: true,
              value: method
            });
          } else {
            object[name] = method;
          }
        });
      }
docs: Define configurable, writable and non-enumerable props if they don’t exist.