docs: def paint( self, painter, option, widget ):
          """
          Paints this item to the system.
          
          :param      painter | <QPainter>
                      option  | <QStyleOptionGraphicItem>
                      widget  | <QWidget>
          """
          style       = self.itemStyle()
          ItemStyle   = self.treeItem().ItemStyle
          
          if ( style == ItemStyle.Group ):
              self.paintGroup( painter )
          
          elif ( style == ItemStyle.Milestone ):
              self.paintMilestone( painter )
          
          else:
              self.paintNormal( painter )