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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 pan_delta(self, d):
 """Pan the view by a given amount."""

        dx, dy = d

        pan_x, pan_y = self.pan
        zoom_x, zoom_y = self._zoom_aspect(self._zoom)

        self.pan = (pan_x + dx / zoom_x, pan_y + dy / zoom_y)
        self.update()