def init(with_threads=1):
    """Initialize threading.

    Don't bother calling this.  If it needs to happen, it will happen.
    """
    global threaded, _synchLockCreator, XLock

    if with_threads:
        if not threaded:
            if threadingmodule is not None:
                threaded = True

                class XLock(threadingmodule._RLock, object):
                    def __reduce__(self):
                        return (unpickle_lock, ())

                _synchLockCreator = XLock()
            else:
                raise RuntimeError("Cannot initialize threading, platform lacks thread support")
    else:
        if threaded:
            raise RuntimeError("Cannot uninitialize threads")
        else:
            pass
Initialize threading.

    Don't bother calling this.  If it needs to happen, it will happen.
    
stackoverflow/venv/lib/python3.6/site-packages/twisted/python/threadable.py