def bin(args):
    """
    %prog bin filename filename.bin

    Serialize counts to bitarrays.
    """
    from bitarray import bitarray
    p = OptionParser(bin.__doc__)
    opts, args = p.parse_args(args)

    if len(args) != 2:
        sys.exit(not p.print_help())

    inp, outp = args
    fp = must_open(inp)
    fw = must_open(outp, "w")
    a = bitarray()
    for row in fp:
        c = row.split()[-1]
        a.append(int(c))
    a.tofile(fw)
    fw.close()
%prog bin filename filename.bin

    Serialize counts to bitarrays.