If you need multi-core for performance, first you should rewrite in a compiled language instead of Python. Java/C/C++/Go/FORTRAN/whatever will run 10 to 20 times faster before even worrying about running multi-core.
I love Python. But, it's good to remember sometimes that it runs at about 1% efficiency compared to well-optimized C. So, you paid for a whole machine and you are utilizing 0.01%. That's fine for a lot of tasks; especially tasks that are 99% I/O-bound or tasks that are just coordinating big C libraries to do 99% of the work. Just good to remember sometimes...