def METHOD_NAME(self):
    """
    Return the homogeneous rescaling to apply after the coordinate
    substitution.
    OUTPUT:
    A polynomial. See the example below.
    EXAMPLES::
        sage: R.<a,b,c> = QQ[]
        sage: cubic =  a^3+7*b^3+64*c^3
        sage: P = [2,2,-1]
        sage: f = EllipticCurve_from_cubic(cubic, P, morphism=True).inverse()
        sage: f.post_rescaling()
        -1/7
    So here is what it does. If we just plug in the coordinate
    transformation, we get the defining polynomial up to
    scale. This method returns the overall rescaling of the
    equation to bring the result into the standard form::
        sage: cubic(f.defining_polynomials())
        7*x^3 - 7*y^2*z + 1806336*y*z^2 - 155373797376*z^3
        sage: cubic(f.defining_polynomials()) * f.post_rescaling()
        -x^3 + y^2*z - 258048*y*z^2 + 22196256768*z^3
    """
    return self._post