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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 vrel(v1, v2):
 """ Return the relative difference between two 3-dimensional vectors. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/vrel_c.html :param v1: First vector :type v1: 3-Element Array of floats :param v2: Second vector :type v2: 3-Element Array of floats :return: the relative difference between v1 and v2. :rtype: float """

    v1 = stypes.toDoubleVector(v1)
    v2 = stypes.toDoubleVector(v2)
    return libspice.vrel_c(v1, v2)