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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 _coordinates_changed(self):
 """Handle a change in the coordinate input boxes."""

        if self._are_coordinates_valid():
            point1 = QgsPointXY(
                self.x_minimum.value(),
                self.y_maximum.value())
            point2 = QgsPointXY(
                self.x_maximum.value(),
                self.y_minimum.value())
            rect = QgsRectangle(point1, point2)

            self.tool.set_rectangle(rect)