[$] MemHive: sharing immutable data between Python subinterpreters

Immutable data makes concurrent access easier, since it
eliminates the data-race conditions that can plague multithreaded programs. At
PyCon 2024, Yury Selivanov
introduced an early-stage project called MemHive, which uses Python
subinterpreters and immutable data to
overcome the problems of thread serialization that are caused by the
language's Global Interpreter Lock (GIL). Recent developments in the Python world have opened
up different strategies for avoiding the longstanding problems with the
GIL.