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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 sky_dist(src1, src2):
 """ Great circle distance between two sources. A check is made to determine if the two sources are the same object, in this case the distance is zero. Parameters src1, src2 : object Two sources to check. Objects must have parameters (ra,dec) in degrees. Returns ------- distance : float The distance between the two sources. See Also -------- :func:`AegeanTools.angle_tools.gcd` """


    if np.all(src1 == src2):
        return 0
    return gcd(src1.ra, src1.dec, src2.ra, src2.dec)