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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 _mass2_from_mchirp_mass1(mchirp, mass1):
 r"""Returns the secondary mass from the chirp mass and primary mass. As this is a cubic equation this requires finding the roots and returning the one that is real. Basically it can be shown that: .. math:: m_2^3 - a(m_2 + m_1) = 0, where .. math:: a = \frac{\mathcal{M}^5}{m_1^3}. This has 3 solutions but only one will be real. """

    a = mchirp**5 / mass1**3
    roots = numpy.roots([1,0,-a,-a*mass1])
    # Find the real one
    real_root = roots[(abs(roots - roots.real)).argmin()]
    return real_root.real