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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 metrics(self, raw=False):
 """Get metrics on producer performance. This is ported from the Java Producer, for details see: https://kafka.apache.org/documentation/#producer_monitoring Warning: This is an unstable interface. It may change in future releases without warning. """

        if raw:
            return self._metrics.metrics.copy()

        metrics = {}
        for k, v in six.iteritems(self._metrics.metrics.copy()):
            if k.group not in metrics:
                metrics[k.group] = {}
            if k.name not in metrics[k.group]:
                metrics[k.group][k.name] = {}
            metrics[k.group][k.name] = v.value()
        return metrics