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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 ND_SDR_available(ID, SDR):
 """ Return an available ND given an ID and a schedule. Takes the values of the array, compares to the ID, and finds the index of the first value greater or equal. """

    for i in range(len(np.array(ID_SDR_all_available(SDR)))):
        if np.array(ID_SDR_all_available(SDR))[i] >= (ID.to(u.inch)).magnitude:
            return ND_all_available()[i]