What happens after cythonizing a python ros2 package?

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I have a project that is a python based ros2 project. in order to reduce runtimes I decided to cythonize my packages, and my question is what happens after cythonizing? does ros2 automatically know to use the cythonized files or does it use the original python files unless I do additional steps?

what I mean is, after cythonizing I runt the ros2 run pkg_name node_name method to run my nodes and I want to make sure I use the new cythonized files and not the original python ones. and I wanted to ask how do I make sure that actually happens.