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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 dvnorm(state):
 """ Function to calculate the derivative of the norm of a 3-vector. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/dvnorm_c.html :param state: A 6-vector composed of three coordinates and their derivatives. :type state: 6-Element Array of floats :return: The derivative of the norm of a 3-vector. :rtype: float """

    assert len(state) is 6
    state = stypes.toDoubleVector(state)
    return libspice.dvnorm_c(state)