code: function (dest, src) {
          var prop;
  
          // update or add values from src
          for (prop in src) {
              if (src.hasOwnProperty(prop)) {
                  dest[prop] = src[prop];
              }
          }
  
          // remove values that no longer exist
          for (prop in dest) {
              if (dest.hasOwnProperty(prop) && !src.hasOwnProperty(prop)) {
                  delete dest[prop];
              }
          }
  
          return dest;
      }
docs: Copies attributes from source object to destination object.
  
  @param dest
  @param src
  
  @return {Object}