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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 cylrec(r, lon, z):
 """ Convert from cylindrical to rectangular coordinates. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/cylrec_c.html :param r: Distance of a point from z axis. :type r: float :param lon: Angle (radians) of a point from xZ plane. :type lon: float :param z: Height of a point above xY plane. :type z: float :return: Rectangular coordinates of the point. :rtype: 3-Element Array of floats """

    r = ctypes.c_double(r)
    lon = ctypes.c_double(lon)
    z = ctypes.c_double(z)
    rectan = stypes.emptyDoubleVector(3)
    libspice.cylrec_c(r, lon, z, rectan)
    return stypes.cVectorToPython(rectan)