code: public Aggregate DISTINCT() {
  		ReturnExpression rx = (ReturnExpression)this.astNode;
  		ReturnAggregate ra = (ReturnAggregate) rx.getReturnValue();
  		ra.setDistinct();
  		Aggregate ret = new Aggregate(rx);
  		return ret;
  	}
docs: <div color='red' style="font-size:24px;color:red"><b><i><u>JCYPHER</u></i></b></div>
  <div color='red' style="font-size:18px;color:red"><i>return unique results</i></div>
  <div color='red' style="font-size:18px;color:red"><i>e.g. ...aggregate().<b>DISTINCT().sum(n.property("eyeColor"))</b></i></div>
  <br/>