code: function(_other) {
        return this.$action(function() {
          for(var tmp in _other) {
            if (_other.hasOwnProperty(tmp) && tmp[0] !== '$') {
              this[tmp] = _other[tmp];
            }
          }
        });
      }
docs: @memberof RecordApi#
  
  @description Copyies another object's non-private properties.
  
  This method runs inside the promise chain, so calling
  
  ```javascript
  Bike.$find(1).$extend({ size: "L" }).$save();
  ```
  Will first fetch the bike data and after it is loaded the new size will be applied and then the
  updated model saved.
  
  @param {object} _other Object to merge.
  @return {RecordApi} self