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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 vrotv(v, axis, theta):
 """ Rotate a vector about a specified axis vector by a specified angle and return the rotated vector. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/vrotv_c.html :param v: Vector to be rotated. :type v: 3-Element Array of floats :param axis: Axis of the rotation. :type axis: 3-Element Array of floats :param theta: Angle of rotation (radians). :type theta: float :return: Result of rotating v about axis by theta :rtype: 3-Element Array of floats """

    v = stypes.toDoubleVector(v)
    axis = stypes.toDoubleVector(axis)
    theta = ctypes.c_double(theta)
    r = stypes.emptyDoubleVector(3)
    libspice.vrotv_c(v, axis, theta, r)
    return stypes.cVectorToPython(r)