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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 scale_image(self):
 """Scale the image size."""

        new_width = int(self.figcanvas.fwidth *
                        self._scalestep ** self._scalefactor)
        new_height = int(self.figcanvas.fheight *
                         self._scalestep ** self._scalefactor)
        self.figcanvas.setFixedSize(new_width, new_height)