old_contents: from trololio import asyncio, coroutine, From, Return
  from os import environ
  
  
  @coroutine
  def coro_ret(*args):
      raise Return(*args)
  
  
  @coroutine
  def coro_yield(sleep_time):
      yield From(asyncio.sleep(sleep_time))
  
  
  if __name__ == '__main__':
      assert environ.get('PYTHONASYNCIODEBUG') == environ.get('TROLLIUSDEBUG')
  
      loop = asyncio.get_event_loop()
  
      try:
          for x in ([1, 2, 3], None, [None]):
              res = loop.run_until_complete(coro_ret(x))
              assert res == x
  
          loop.run_until_complete(coro_yield(1))
      finally:
          loop.close()
  
new_contents: from trololio import asyncio, coroutine, From, Return
  
  
  @coroutine
  def coro_ret(*args):
      raise Return(*args)
  
  
  @coroutine
  def coro_yield(sleep_time):
      yield From(asyncio.sleep(sleep_time))
  
  
  if __name__ == '__main__':
      loop = asyncio.get_event_loop()
  
      try:
          for x in ([1, 2, 3], None, [None]):
              res = loop.run_until_complete(coro_ret(x))
              assert res == x
  
          loop.run_until_complete(coro_yield(1))
      finally:
          loop.close()
  
subject: Remove invalid assertion