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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 overview(index, start, end):
 """Compute metrics in the overview section for enriched git indexes. Returns a dictionary. Each key in the dictionary is the name of a metric, the value is the value of that metric. Value can be a complex object (eg, a time series). :param index: index object :param start: start date to get the data from :param end: end date to get the data upto :return: dictionary with the value of the metrics """


    results = {
        "activity_metrics": [Commits(index, start, end)],
        "author_metrics": [Authors(index, start, end)],
        "bmi_metrics": [],
        "time_to_close_metrics": [],
        "projects_metrics": []
    }

    return results