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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 rbf(ra, coeff, mag):
 """ Calculate the median ground motion for a given magnitude and distance :param ra: Distance value [km] :param coeff: The set of coefficients :param mag: Magnitude value :returns: """

    a1ca, a1cb, a1cc, a1cd, a1ce, a2ca, a2cb, a2cc, a2cd, a2ce = gc(coeff, mag)
    term1 = a1ca + a1cb * mag + a1cc * np.log(ra + a1cd*np.exp(a1ce*mag))
    term2 = a2ca + a2cb * mag
    term3 = a2cd*np.exp(a2ce*mag)
    return np.exp((term1 - term2) / a2cc) - term3