def fastareorder_parser(subparsers):
    """
    Parser for the fastareorder tool.
    """
    parser = subparsers.add_parser('fastareorder', help=
        'reorder sequences in a FASTA file', description=
        'Reorder sequences in a FASTA file.')
    parser.add_argument('fasta', help='a FASTA file of sequences to reorder')
    parser.add_argument('order_file', help='a file with the sequence order')
    parser.add_argument('output', help=
        'an output FASTA file of reordered sequences')
    parser.add_argument('-i', '--ignore_missing', action='store_true', help
        =
        'ignore sequences in the specified order file that are missing in the input FASTA file'
        )
