def _ld_job(jobs, plink):
    """Private function to run plink, see filter_by_ld().

    Parameters
    ----------
    jobs : list_of_tuple
        A list of job arguments:
            (snp, comp_snps, chrom, r2, populations, raise_on_error, logfile)
    plink : PLINK
        An initialized plink class
    """
    snp_results = {}
    for job in jobs:
        snp_results[job[0]] = plink.one_to_many(*job)
    return snp_results