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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 build_parser(parser):
 """ Add shared arguments to the convert or mogrify parser. """

    add_options(parser)
    parser.add_argument('source_file', type=common.FileType('rt'),
                        help="Input sequence file")
    parser.add_argument('dest_file', help="Output file")

    return parser