Remove a metric producer.

        :type metric_producer: :class: 'MetricProducer'
        :param metric_producer: The metric producer to remove.

def remove(self, metric_producer):
        """Remove a metric producer.

        :type metric_producer: :class: 'MetricProducer'
        :param metric_producer: The metric producer to remove.
        """
        if metric_producer is None:
            raise ValueError
        try:
            with self.mp_lock:
                self.metric_producers.remove(metric_producer)
        except KeyError:
            pass