getnikola/plugins — pull request #36 by ivanteoh (2014-03-09 11:25:58+00:00)
Title: Fix max argument allowed.

Now I understand optional_arguments is nothing to do with option_spec. All arguments (both required and optional) are separated by space on the first line. Since there is only one required argument with space. I have to set 'final_argument_whitespace' to true.