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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 ducrss(s1, s2):
 """ Compute the unit vector parallel to the cross product of two 3-dimensional vectors and the derivative of this unit vector. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/ducrss_c.html :param s1: Left hand state for cross product and derivative. :type s1: 6-Element Array of floats :param s2: Right hand state for cross product and derivative. :type s2: 6-Element Array of floats :return: Unit vector and derivative of the cross product. :rtype: 6-Element Array of floats """

    assert len(s1) is 6 and len(s2) is 6
    s1 = stypes.toDoubleVector(s1)
    s2 = stypes.toDoubleVector(s2)
    sout = stypes.emptyDoubleVector(6)
    libspice.ducrss_c(s1, s2, sout)
    return stypes.cVectorToPython(sout)