The whole point here is we need parallel processing, and Python cannot provide this in a single process due to the GIL. Flask applications depend on the workloa

The whole point here is we need parallel processing, and Python cannot provide this in a single process due to the GIL. Flask applications depend on the workload being I/O bound, so it can achieve concurrency where parallelism is not required. If you built a process that is CPU bound in Python code in Flask, you'd find it could not achieve much concurrency at all.