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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def generate_excise_subparser(subparsers):
 """Adds a sub-command parser to `subparsers` to excise n-grams from witnesses."""

    parser = subparsers.add_parser(
        'excise', description=constants.EXCISE_DESCRIPTION,
        help=constants.EXCISE_HELP)
    parser.set_defaults(func=excise)
    utils.add_common_arguments(parser)
    parser.add_argument('ngrams', metavar='NGRAMS',
                        help=constants.EXCISE_NGRAMS_HELP)
    parser.add_argument('replacement', metavar='REPLACEMENT',
                        help=constants.EXCISE_REPLACEMENT_HELP)
    parser.add_argument('output', metavar='OUTPUT',
                        help=constants.EXCISE_OUTPUT_HELP)
    utils.add_corpus_arguments(parser)
    parser.add_argument('works', metavar='WORK',
                        help=constants.EXCISE_WORKS_HELP, nargs='+')