code: def maxNotchSize( self, orientation ):
          
          metrics = QFontMetrics(QApplication.font())
          
          if orientation == Qt.Vertical:
              notch = ''
              for n in self.notches():
                  if len(nativestring(n)) > len(nativestring(notch)):
                      notch = nativestring(n)
              
              return metrics.width(notch)
          else:
              return metrics.height()
docs: Returns the maximum size for this ruler based on its notches and the
          given orientation.
          
          :param      orientation | <Qt.Orientation>
          
          :return     <int>