code: def set_shell(self, svc_ref):
          
          if svc_ref is None:
              return
  
          with self._lock:
              # Get the service
              self._shell_ref = svc_ref
              self._shell = self._context.get_service(self._shell_ref)
  
              # Set the readline completer
              if readline is not None:
                  readline.set_completer(self.readline_completer)
  
              # Set the flag
              self._shell_event.set()
docs: Binds the given shell service.
  
          :param svc_ref: A service reference