value = runInThread(fn, args...) for Python

run_in_thread.py

def runInThread(fn, *args, **kw):
    """Execute fn(*args, **kw) in a new thread context and return the result.

    The execution is synchronous, i.e. blocking.

    Typical use cases for runInThread will be the inspection of side effects
    that are normally invisible to other threads until you commit a transaction
    or something like that.
    """
    # Aargh! Why can't threading.Thread(target=fn).join() return the result of
    # fn()?  This whole function should be a one-liner, dammit!
    result = []
    error = []
    def wrapper():
        try:
            result.append(fn(*args, **kw))
        except:
            error.extend(sys.exc_info())
    t = threading.Thread(target=wrapper)
    t.start()
    t.join()
    if error:
        raise error[0], error[1], error[2]
    return result[0]