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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _try_trigger_before_first_request_funcs(self):
 # pylint: disable=C0103 """Runs each function from ``self.before_first_request_funcs`` once and only once."""

        if self._after_first_request_handled:
            return
        else:
            with self._before_first_request_lock:
                if self._after_first_request_handled:
                    return
                for func in self._before_first_request_funcs:
                    func()
                self._after_first_request_handled = True