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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 cart2sph(x, y, z):
 """ Converts cartesian coordinates `x`, `y`, `z` into a longitude and latitude. x=0, y=0, z=0 is assumed to correspond to the center of the globe. Returns lon and lat in radians. Parameters `x`, `y`, `z` : Arrays of cartesian coordinates Returns ------- lon : Longitude in radians lat : Latitude in radians """

    r = np.sqrt(x**2 + y**2 + z**2)
    lat = np.arcsin(z/r)
    lon = np.arctan2(y, x)
    return lon, lat