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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 angular_distance_fast(ra1, dec1, ra2, dec2):
 """ Compute angular distance using the Haversine formula. Use this one when you know you will never ask for points at their antipodes. If this is not the case, use the angular_distance function which is slower, but works also for antipodes. :param lon1: :param lat1: :param lon2: :param lat2: :return: """


    lon1 = np.deg2rad(ra1)
    lat1 = np.deg2rad(dec1)
    lon2 = np.deg2rad(ra2)
    lat2 = np.deg2rad(dec2)
    dlon = lon2 - lon1
    dlat = lat2 - lat1

    a = np.sin(dlat/2.0)**2 + np.cos(lat1) * np.cos(lat2) * np.sin(dlon /2.0)**2
    c = 2 * np.arcsin(np.sqrt(a))
    return np.rad2deg(c)