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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 keyPressEvent(self, event):

 """Reimplemented to handle key events"""

        ctrl = event.modifiers() & Qt.ControlModifier
        shift = event.modifiers() & Qt.ShiftModifier
        if event.key() in (Qt.Key_Enter, Qt.Key_Return):
            self.find.emit()
        elif event.key() == Qt.Key_F and ctrl and shift:
            # Toggle find widgets
            self.parent().toggle_visibility.emit(not self.isVisible())
        else:
            QWidget.keyPressEvent(self, event)