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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 mktmpenv_cmd(argv):
 """Create a temporary virtualenv."""

    parser = mkvirtualenv_argparser()
    env = '.'
    while (workon_home / env).exists():
        env = hex(random.getrandbits(64))[2:-1]

    args, rest = parser.parse_known_args(argv)

    mkvirtualenv(env, args.python, args.packages, requirements=args.requirements,
                 rest=rest)
    print('This is a temporary environment. It will be deleted when you exit')
    try:
        if args.activate:
            # only used for testing on windows
            shell(env)
    finally:
        return rmvirtualenvs([env])