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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 eigs_s(infile="", dir_path='.'):
 """ Converts eigenparamters format data to s format Parameters ___________________ Input: file : input file name with eigenvalues (tau) and eigenvectors (V) with format: tau_1 V1_dec V1_inc tau_2 V2_dec V2_inc tau_3 V3_dec V3_inc Output the six tensor elements as a nested array """

    file = os.path.join(dir_path, infile)
    eigs_data = np.loadtxt(file)
    Ss = []
    for ind in range(eigs_data.shape[0]):
        tau, Vdirs = [], []
        for k in range(0, 9, 3):
            tau.append(eigs_data[ind][k])
            Vdirs.append([eigs_data[ind][k+1], eigs_data[ind][k+2]])
        s = list(pmag.doeigs_s(tau, Vdirs))
        Ss.append(s)
    return Ss