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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 xyz2stereonet(x, y, z):
 """ Converts x, y, z in _world_ cartesian coordinates into lower-hemisphere stereonet coordinates. Parameters x, y, z : array-likes Sequences of world coordinates Returns ------- lon, lat : arrays Sequences of longitudes and latitudes (in radians) """

    x, y, z = np.atleast_1d(x, y, z)
    return cart2sph(-z, x, y)