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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 __get_total_response_time(meta_datas_expanded):
 """ caculate total response time of all meta_datas """

    try:
        response_time = 0
        for meta_data in meta_datas_expanded:
            response_time += meta_data["stat"]["response_time_ms"]

        return "{:.2f}".format(response_time)

    except TypeError:
        # failure exists
        return "N/A"