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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 main(func=None, argv=None, input_stream=stdin, output_stream=stdout, error_stream=stderr, exit=True):
 """runs a function as a command. runs a function as a command - reading input from `input_stream`, writing output into `output_stream` and providing arguments from `argv`. Example Usage: more examples on `README.md` :param callable func: the function to execute, must be decorated by `@cbox.cmd` or `@cbox.stream`. :param list[str] argv: command arguments (default `sys.argv`) :param input_stream: readable file-like object (default `stdin`) :param output_stream: writable file-like object (default `stdout`) :param error_stream: writable file-like object (default `stderr`) :param bool exit: if True, exits (i.e. `sys.exit(exitcode)`) with the `exitcode`, else returns the `exitcode`. the code is 0 if no errors, else 2. :return: the exit code if `exit` is False, else raises `SystemExit(code)` """

    executor = executors.get_func_executor(func)
    exitcode = executor(func, argv, input_stream, output_stream, error_stream)

    if exit:
        sys.exit(exitcode)
    return exitcode