code: function initializeEntityPrototype(proto) {
  
          proto.getProperty = function(propertyName) {
              return this[propertyName];
          };
  
          proto.setProperty = function (propertyName, value) {
              //if (!this._backingStore.hasOwnProperty(propertyName)) {
              //    throw new Error("Unknown property name:" + propertyName);
              //}
              this[propertyName] = value;
              // allow setProperty chaining.
              return this;
          };
  
          movePropDefsToProto(proto);
      }
docs: ////////////////////////////////// This method is called during Metadata initialization