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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 mxv(m1, vin):
 """ Multiply a 3x3 double precision matrix with a 3-dimensional double precision vector. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/mxv_c.html :param m1: 3x3 double precision matrix. :type m1: 3x3-Element Array of floats :param vin: 3-dimensional double precision vector. :type vin: 3-Element Array of floats :return: 3-dimensional double precision vector. :rtype: 3-Element Array of floats """

    m1 = stypes.toDoubleMatrix(m1)
    vin = stypes.toDoubleVector(vin)
    vout = stypes.emptyDoubleVector(3)
    libspice.mxv_c(m1, vin, vout)
    return stypes.cVectorToPython(vout)