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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 vminus(vin):
 """ Negate a double precision 3-dimensional vector. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/vminus_c.html :param vin: Vector to be negated. :type vin: 3-Element Array of floats :return: Negated vector -v1. :rtype: 3-Element Array of floats """

    vin = stypes.toDoubleVector(vin)
    vout = stypes.emptyDoubleVector(3)
    libspice.vminus_c(vin, vout)
    return stypes.cVectorToPython(vout)