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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 collect_metrics(local_evaluator=None, remote_evaluators=[], timeout_seconds=180):
 """Gathers episode metrics from PolicyEvaluator instances."""


    episodes, num_dropped = collect_episodes(
        local_evaluator, remote_evaluators, timeout_seconds=timeout_seconds)
    metrics = summarize_episodes(episodes, episodes, num_dropped)
    return metrics