for @eugeneliukindev

questions:

• why the SyncWorker.wait integer return type (found nothing in commit eugeneliukindev@f23abec)?

notes on things I would like to modify:

• match stdlib wsgiref in that start_response accepts optional exc_info
• FileWrapper.__getitem__ is odd, mark the argument Never
• restrict load_class to only classes it is used for via gunicorn.conf.py
• clarify that write_error shall not inject arbitrary str data
• most timeout are actually float not int, and gunicorn/workers/sync.py actually uses this
• timeout_ctx must return a context wrapper
• overriding ThreadWorker.poller is legitimate
• handle_request(listener_name) can be either (addr,port) tuples or string (e.g. UNIX sockets)