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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 vpack(x, y, z):
 """ Pack three scalar components into a vector. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/vpack_c.html :param x: first scalar component :type x: float :param y: second scalar component :type y: float :param z: third scalar component :type z: float :return: Equivalent 3-vector. :rtype: 3-Element Array of floats """

    x = ctypes.c_double(x)
    y = ctypes.c_double(y)
    z = ctypes.c_double(z)
    vout = stypes.emptyDoubleVector(3)
    libspice.vpack_c(x, y, z, vout)
    return stypes.cVectorToPython(vout)