[3.12] gh-124594: Create and reuse the same context for the entire asyncio REPL session (GH-124595)

[miss-islington]

(cherry picked from commit 67e01a4)

Co-authored-by: Bartosz Sławecki [email protected]
Co-authored-by: Andrew Svetlov [email protected]

• Issue: Every input in asyncio REPL (wrongly) runs in a separate PEP 567 context #124594

[bswck]

The failure seems pretty quirky.

asyncio REPL 3.12.7+ (remotes/pull/124849/merge-dirty:fd216e1, Oct  1 2024, 14:24:15) [GCC 11.4.0] on linux
Use "await" directly instead of "asyncio.run()".
Type "help", "copyright", "credits" or "license" for more information.
>>> import asyncio
>>> >>> >>> ...   File "<console>", line 2
    await set_var()
    ^^^^^
SyntaxError: invalid syntax
>>> toplevel contextvar test: failed
>>>
exiting asyncio REPL...
>>>

(copied from CI)
I'll inspect that further on the 3.12 branch in a couple days.