code: function() {
  		this._groups = [];
  		var group_labels = this.timescale.getGroupLabels();
  
  		if (group_labels) {
  			this.options.has_groups = true;
  			for (var i = 0; i < group_labels.length; i++) {
  				this._createGroup(group_labels[i]);
  			}
  		}
  
  	}
docs: /*	Groups
  ==================================================