Future task implementation in Python

future.py

class Future(object):

    def __init__(self, func, *args, **kwargs):
        self._lock = threading.Lock()
        self._thread = threading.Thread(target=self._locked(func), args=args,
                                        kwargs=kwargs)
        self._result = None
        self._done = False

    def _locked(self, func):
        @functools.wraps(func)
        def wrapper(*args, **kwargs):
            self._lock.acquire()
            try:
                self._result = func(*args, **kwargs)
                self._done = True
            finally:
                self._lock.release()
        return wrapper

    def __call__(self):
        # Block until the lock is acquired
        self._lock.acquire()
        try:
            return self._result
        finally:
            self._lock.release()

    def start(self):
        return self._thread.start()

    @property
    def done(self):
        return self._done