using python interpreters per thread in C++ program

[ganesh]

> Did you remeber to acquire the GIL? The GIL is global to the process

No, I did not use GIL.

-- Why do we need to use GIL even though python is private to each
thread?
-- For using GIL, do we need to initialize GIL at startup and destroy/
finalize it at end?
-- With GIL, we are not achieiving concurrent operations on python
interpreters across threads. When it comes to calling Py-C APIs,
program is working like in a single threaded mode. Is there any way,
we can avoid the GIL locking, etc?

Please guide. Thanks.