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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 latcyl(radius, lon, lat):
 """ Convert from latitudinal coordinates to cylindrical coordinates. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/latcyl_c.html :param radius: Distance of a point from the origin. :type radius: :param lon: Angle of the point from the XZ plane in radians. :param lat: Angle of the point from the XY plane in radians. :return: (r, lonc, z) :rtype: tuple """

    radius = ctypes.c_double(radius)
    lon = ctypes.c_double(lon)
    lat = ctypes.c_double(lat)
    r = ctypes.c_double()
    lonc = ctypes.c_double()
    z = ctypes.c_double()
    libspice.latcyl_c(radius, lon, lat, ctypes.byref(r), ctypes.byref(lonc),
                      ctypes.byref(z))
    return r.value, lonc.value, z.value