def _contour(self):
"""Returns contour path."""
ppath = QPainterPath()
rect = self.contentsRect()
margin = 5
ppath.addRoundedRect(rect.left() - margin, rect.top() - margin,
rect.width() + 2 * margin,
rect.height() + 2 * margin, 15, 15)
arrowpath = QPainterPath()
arrowpath.moveTo(rect.center().x(), self.height())
arrowpath.lineTo(rect.center().x() - 10, rect.bottom())
arrowpath.lineTo(rect.center().x() + 10, rect.bottom())
arrowpath.lineTo(rect.center().x(), self.height())
ppath = ppath.united(arrowpath)
return ppath
