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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 affine(self, pixelbuffer=0):
 """ Return an Affine object of tile. - pixelbuffer: tile buffer in pixels """

        return Affine(
            self.pixel_x_size,
            0,
            self.bounds(pixelbuffer).left,
            0,
            -self.pixel_y_size,
            self.bounds(pixelbuffer).top
        )