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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_common_args(parser, is_create=True):
 """If is_create is True, protocol and action become mandatory arguments. CreateCommand = is_create : True UpdateCommand = is_create : False """

    parser.add_argument(
        '--name',
        help=_('Name for the firewall rule.'))
    parser.add_argument(
        '--description',
        help=_('Description for the firewall rule.'))
    parser.add_argument(
        '--source-ip-address',
        help=_('Source IP address or subnet.'))
    parser.add_argument(
        '--destination-ip-address',
        help=_('Destination IP address or subnet.'))
    parser.add_argument(
        '--source-port',
        help=_('Source port (integer in [1, 65535] or range in a:b).'))
    parser.add_argument(
        '--destination-port',
        help=_('Destination port (integer in [1, 65535] or range in '
               'a:b).'))
    utils.add_boolean_argument(
        parser, '--enabled', dest='enabled',
        help=_('Whether to enable or disable this rule.'))
    parser.add_argument(
        '--protocol', choices=['tcp', 'udp', 'icmp', 'any'],
        required=is_create,
        type=utils.convert_to_lowercase,
        help=_('Protocol for the firewall rule.'))
    parser.add_argument(
        '--action',
        required=is_create,
        type=utils.convert_to_lowercase,
        choices=['allow', 'deny', 'reject'],
        help=_('Action for the firewall rule.'))