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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 add_jardiff_optgroup(parser):
 """ option group specific to the tests in jardiff """


    og = parser.add_argument_group("JAR Checking Options")

    og.add_argument("--ignore-jar-entry", action="append", default=[])

    og.add_argument("--ignore-jar-signature",
                    action="store_true", default=False,
                    help="Ignore JAR signing changes")

    og.add_argument("--ignore-manifest",
                    action="store_true", default=False,
                    help="Ignore changes to manifests")

    og.add_argument("--ignore-manifest-subsections",
                    action="store_true", default=False,
                    help="Ignore changes to manifest subsections")

    og.add_argument("--ignore-manifest-key",
                    action="append", default=[],
                    help="case-insensitive manifest keys to ignore")