Speed up reading multiple pickle files

I have a lot of pickle files. Currently I read them in a loop but it takes a lot of time. I would like to speed it up but don't have any idea how to do that.

Multiprocessing wouldn't work because in order to transfer data from a child subprocess to the main process data need to be serialized (pickled) and deserialized.

Using threading wouldn't help either because of GIL.

I think that the solution would be some library written in C that takes a list of files to read and then runs multiple threads (without GIL). Is there something like this around?

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