def dots_to_empty_cells(config, tsv_fpath):
    """Put dots instead of empty cells in order to view TSV with column -t
    """
    def proc_line(l, i):
        while '\t\t' in l:
            l = l.replace('\t\t', '\t.\t')
        return l
    return iterate_file(config, tsv_fpath, proc_line, suffix='dots')