code: def receive(args, reactor=reactor, _debug_stash_wormhole=None):
      
      r = Receiver(args, reactor)
      d = r.go()
      if _debug_stash_wormhole is not None:
          _debug_stash_wormhole.append(r._w)
      return d
docs: I implement 'wormhole receive'. I return a Deferred that fires with
      None (for success), or signals one of the following errors:
      * WrongPasswordError: the two sides didn't use matching passwords
      * Timeout: something didn't happen fast enough for our tastes
      * TransferError: the sender rejected the transfer: verifier mismatch
      * any other error: something unexpected happened