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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 fRD( a, M):
 """Calculate the ring-down frequency for the final Kerr BH. Using Eq. 5.5 of Main paper"""

    f = (lal.C_SI**3.0 / (2.0*lal.PI*lal.G_SI*M*lal.MSUN_SI)) * (1.5251 - 1.1568*(1.0-a)**0.1292)
    return f