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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 qxq(q1, q2):
 """ Multiply two quaternions. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/qxq_c.html :param q1: First SPICE quaternion. :type q1: 4-Element Array of floats :param q2: Second SPICE quaternion. :type q2: 4-Element Array of floats :return: Product of q1 and q2. :rtype: 4-Element Array of floats """

    q1 = stypes.toDoubleVector(q1)
    q2 = stypes.toDoubleVector(q2)
    vout = stypes.emptyDoubleVector(4)
    libspice.qxq_c(q1, q2, vout)
    return stypes.cVectorToPython(vout)