def merge(self, other: 'Metrics') -> None:
        """Merge 'other' metrics into this one."""
        self._accumulated_cost += other.accumulated_cost
        self._costs += other._costs
        # use the property so older picked objects that lack the field won't crash
        self.token_usages += other.token_usages
        self.response_latencies += other.response_latencies

        # Merge accumulated token usage using the __add__ operator
        self._accumulated_token_usage = (
            self.accumulated_token_usage + other.accumulated_token_usage
        )
Merge 'other' metrics into this one.
openhands/llm/metrics.py