You have some options.
You can create your own obfuscation method comprised of existing encryption tools...i.e. openssl. But, beware, it will likely take you a considerable amount of time to complete this type of project.
It'll require you to map out how you're going to enclosed the "passwords/passkeys" within the obfuscated code in such a way that no one, except you, can get to it. It'll be preferable if even you cant get to it.
Then, you need to add in some logic that will cause the script to protect itself from inquisitive users who may try to pry it apart. And equally as important, whatever method you come up with must not add significantly to the execution time of the script.
This may sound impossible, but i think its doable. You just have to be motivated and have enough time on your hands.
Or, if you want a shortcut, you can try pasting a sample unix based python script to this site, and see if you can break their code and unveil your "hidden" code.