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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 fnc(ra, *args):
 """ Function used in the minimisation problem. :param ra: Semi-axis of the ellipses used in the Yu et al. :returns: The absolute difference between the epicentral distance and the adjusted distance """

    #
    # epicentral distance
    repi = args[0]
    #
    # azimuth
    theta = args[1]
    #
    # magnitude
    mag = args[2]
    #
    # coefficients
    coeff = args[3]
    #
    # compute the difference between epicentral distances
    rb = rbf(ra, coeff, mag)
    t1 = ra**2 * (np.sin(np.radians(theta)))**2
    t2 = rb**2 * (np.cos(np.radians(theta)))**2
    xx = ra * rb / (t1+t2)**0.5
    return xx-repi