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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 is_orthonormal(self):
 """True if the transform is orthonormal, which means that the transform represents a rigid motion, which has no effective scaling or shear. Mathematically, this means that the axis vectors of the transform matrix are perpendicular and unit-length. Applying an orthonormal transform to a shape always results in a congruent shape. """

        a, b, c, d, e, f, g, h, i = self
        return (
            self.is_conformal
            and abs(1.0 - (a * a + d * d)) < EPSILON
            and abs(1.0 - (b * b + e * e)) < EPSILON
        )