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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 read_metrics_file(path: str) -> List[Dict[str, Any]]: """ Reads lines metrics file and returns list of mappings of key and values. :param path: File to read metric values from. :return: Dictionary of metric names (e.g. perplexity-train) mapping to a list of values. """

    with open(path) as fin:
        metrics = [parse_metrics_line(i, line.strip()) for i, line in enumerate(fin, 1)]
    return metrics