docs: def trigger(self, event, *args, **kw):
          """
          Triggers event observers for the given event name,
          passing custom variadic arguments.
          """
          observers = self._pool.get(event)
  
          # If no observers registered for the event, do no-op
          if not observers or len(observers) == 0:
              return None
  
          # Trigger observers coroutines in FIFO sequentially
          for fn in observers:
              # Review: perhaps this should not wait
              yield from fn(*args, **kw)