Easily create asynchronous functions in python using a decorator

async.py

import sys
if sys.version[0] == '2':
	from Queue import Queue
else:
	from queue import Queue
from threading import Thread

class asynchronous(object):
	def __init__(self, func):
		self.func = func

		def threaded(*args, **kwargs):
			self.queue.put(self.func(*args, **kwargs))

		self.threaded = threaded

	def __call__(self, *args, **kwargs):
		return self.func(*args, **kwargs)

	def start(self, *args, **kwargs):
		self.queue = Queue()
		thread = Thread(target=self.threaded, args=args, kwargs=kwargs);
		thread.start();
		return asynchronous.Result(self.queue, thread)

	class NotYetDoneException(Exception):
		def __init__(self, message):
			self.message = message

	class Result(object):
		def __init__(self, queue, thread):
			self.queue = queue
			self.thread = thread

		def is_done(self):
			return not self.thread.is_alive()

		def get_result(self):
			if not self.is_done():
				raise asynchronous.NotYetDoneException('the call has not yet completed its task')

			if not hasattr(self, 'result'):
				self.result = self.queue.get()

			return self.result

		def ensure_finish(self):
			self.thread.join()

if __name__ == '__main__':
	# sample usage
	import time

	@asynchronous
	def long_process(num):
		print('Start: %d' % num)
		time.sleep(2)
		print('End: %d' % num)
		return num * num
	
	results = [long_process.start(i) for i in range(3)]
	for result in results:
		result.ensure_finish()
		if result.is_done():
			print("result {0}".format(result.get_result()))


	result = long_process.start(13)
	# result.ensure_finish()

	try:
		print("result2 {0}".format(result.get_result()))
	except asynchronous.NotYetDoneException as ex:
		print(ex.message)