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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 enterEvent(self, event):
 """ Reimplemented to cancel the hide timer. """

        super(CallTipWidget, self).enterEvent(event)
        if self.as_tooltip:
            self.hide()

        if (self._hide_timer.isActive() and
          self.app.topLevelAt(QCursor.pos()) == self):
            self._hide_timer.stop()