Dealing with multiple context managers

[DeaD_EyE]

Maybe I can also use asynccontextmanager to get the structure I want.

I guess you can do this. Using await in the context, requires to be inside a async function.

EDIT:

You can't mix synchronous and asynchronous context managers :-(
You can stack them only.
Calling a blocking synchronous function in async code, will block the whole event-loop.

What works:

In [35]: @contextlib.asynccontextmanager 
    ...: async def async_ctx(): 
    ...:     print('Entering async context') 
    ...:     await asyncio.sleep(5) 
    ...:     yield 
    ...:     print('Leaving async context') 
    ...:                                                                        

In [36]: @contextlib.contextmanager 
    ...: def sync_ctx(): 
    ...:     print('Entering sync context') 
    ...:     yield 42 
    ...:     print('Leaving sync context')                                      

In [37]: async def run(): 
    ...:     async with async_ctx(): 
    ...:         with sync_ctx() as sync_ret: 
    ...:             print(sync_ret)                                            

In [38]: asyncio.run(run())                                                     
Entering async context
Entering sync context
42
Leaving sync context
Leaving async context