How to Unload model in C++?

Yes, I want to del model and clear the cache, but NOT shutdown the Python process.
In fact, C++ code is used for inference(including pre-processing and post-processing), The Python process(which is running as a service) load model and inference by calling the C++ dynamic library(may have multiple, one dynamic library, one model).
So, Is there a way to delete loaded model without stopping the Python process?
Thanks!