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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 find_omega_min(omega_levelu, Neu, Nl, xiu):
 r"""Find the smallest transition frequency for each field. ([100.0, 200.0], [1, 2], [0, 0]) """

    omega_min = []; iu0 = []; ju0 = []
    for l in range(Nl):
        omegasl = []
        for iu in range(Neu):
            for ju in range(iu):
                if xiu[l, iu, ju] == 1:
                    omegasl += [(omega_levelu[iu]-omega_levelu[ju], iu, ju)]
        omegasl = list(sorted(omegasl))
        omega_min += [omegasl[0][0]]
        iu0 += [omegasl[0][1]]
        ju0 += [omegasl[0][2]]

    return omega_min, iu0, ju0