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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 enhex_app(parser, cmd, args):
 # pragma: no cover """ hex encode a value. """


    parser.add_argument('value', help='the value to hex encode, read from stdin if omitted', nargs='?')
    parser.add_argument(
        '--separator', '-s',
        default='',
        help='the separator to place between hex tuples'
    )
    args = parser.parse_args(args)
    return enhex(pwnypack.main.binary_value_or_stdin(args.value), args.separator)