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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 btn_press_event(self, widget, event):
 """ Function is used for showing Popup menu """

        if event.type == Gdk.EventType.BUTTON_PRESS:
            if event.button.button == 1:
                widget.popup(None, None, None, None,
                             event.button.button, event.time)
            return True
        return False