@classmethod
def from_cli_single_ifo(cls, opt, ifo):
    """Create an InjFilterRejector instance from command-line options."""
    injection_file = opt.injection_file[ifo]
    chirp_time_window = opt.injection_filter_rejector_chirp_time_window[ifo]
    match_threshold = opt.injection_filter_rejector_match_threshold[ifo]
    coarsematch_deltaf = opt.injection_filter_rejector_coarsematch_deltaf[ifo]
    coarsematch_fmax = opt.injection_filter_rejector_coarsematch_fmax[ifo]
    seg_buffer = opt.injection_filter_rejector_seg_buffer[ifo]
    if opt.injection_filter_rejector_f_lower[ifo] is not None:
        f_lower = opt.injection_filter_rejector_f_lower[ifo]
    else:
        f_lower = opt.low_frequency_cutoff
    return cls(injection_file, chirp_time_window, match_threshold, f_lower,
        coarsematch_deltaf, coarsematch_fmax, seg_buffer=seg_buffer)
