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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 default_metric_definitions(cls, toolkit):
 """Provides default metric definitions based on provided toolkit. Args: toolkit(sagemaker.rl.RLToolkit):
 RL Toolkit to be used for training. Returns: list: metric definitions """

        if toolkit is RLToolkit.COACH:
            return [
                {'Name': 'reward-training',
                 'Regex': '^Training>.*Total reward=(.*?),'},
                {'Name': 'reward-testing',
                 'Regex': '^Testing>.*Total reward=(.*?),'}
            ]
        elif toolkit is RLToolkit.RAY:
            float_regex = "[-+]?[0-9]*\.?[0-9]+([eE][-+]?[0-9]+)?"  # noqa: W605, E501 pylint: disable=anomalous-backslash-in-string
            return [
                {'Name': 'episode_reward_mean',
                 'Regex': 'episode_reward_mean: (%s)' % float_regex},
                {'Name': 'episode_reward_max',
                 'Regex': 'episode_reward_max: (%s)' % float_regex}
            ]