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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _onMenuButton(self, evt):
 """Handle menu button pressed."""

        x, y = self.GetPositionTuple()
        w, h = self.GetSizeTuple()
        self.PopupMenuXY(self._menu, x, y+h-4)
                # When menu returned, indicate selection in button
        evt.Skip()