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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 transform(self, X=None, y=None):
 """ Transform an image using an Affine transform with the given shear parameters. Return the transform if X=None. Arguments --------- X : ANTsImage Image to transform y : ANTsImage (optional) Another image to transform Returns ------- ANTsImage if y is None, else a tuple of ANTsImage types Examples -------- """

        # convert to radians and unpack
        shear = [math.pi / 180 * s for s in self.shear]
        shear_x, shear_y = shear

        shear_matrix = np.array([[1, shear_x, 0],
                                 [shear_y, 1, 0]])
        self.tx.set_parameters(shear_matrix)
        if self.lazy or X is None:
            return self.tx
        else:
            return self.tx.apply_to_image(X, reference=self.reference)