Effectively just uses a bit of Any to get a best effort result.

What we'd like to do is to infer the type of CC.job_queue from the Application. However, this is problematic, as the app has a type for the used (sub)class of CallbackContext itself. in particular, when speciyinf a subclass with ContextTypes, we'd like to somehow say CallbackContext[ExtBot, dict, dict, dict, TypeVar('JQ')] + App[…, JobQueue] = CC[…, JobQueue]. Similar things happen on CC.__init__/from_*.
I don't see how this can be achieved with the current status of the typing module, as neither

CCT = TypeVar('CCT', bound=CallbackContext)
def foo(arg: CCT[BT, UD, CD, BD, JQ]):
    pass

nor something like

def foo(arg: CCT) -> CCT.JQ:
   pass

are currently supported.

Hence, CallbackContext.job_queue stays annotated as Optional[JobQueue].

@harshil21 if you can test if pyright works with this as well, that would be nice. We can then maybe merge into #3017 and then merge both together into master.

Example snippet of what I've tested with mypy:

from telegram.ext import ApplicationBuilder, ContextTypes, CallbackContext, ExtBot


class CustomContext(CallbackContext[ExtBot, int, dict, dict]):
    pass


context_types = ContextTypes(user_data=int, context=CustomContext)
app = (
    ApplicationBuilder()
    .token("123456048:AAGpuiaeuiaeuiaeuiaev76jqr45aA")
    .context_types(context_types)
    .job_queue(None)
    .build()
)
reveal_type(app)
reveal_type(app.context_types)
context = CallbackContext(application=app)
reveal_type(context)
reveal_type(context.job_queue)


reveal_type(CallbackContext.from_update(1, app))
reveal_type(CustomContext.from_update(1, app))