code: def emit(signal, *args, **kwargs):
      
      if signal not in __receivers:
          return
  
      receivers = __live_receivers(signal)
  
      for func in receivers:
          func(*args, **kwargs)
docs: Emit a signal by serially calling each registered signal receiver for
      the `signal`.
  
      Note:
          The receiver must accept the *args and/or **kwargs that have been
          passed to it. There expected parameters are not dictated by
          mixbox.
          
      Args:
          signal: A signal identifier or name.
          *args: A variable-length argument list to pass to the receiver.
          **kwargs: Keyword-arguments to pass to the receiver.