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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 project_activity(index, start, end):
 """Compute the metrics for the project activity section of the enriched git index. Returns a dictionary containing a "metric" key. This key contains the metrics for this section. :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 = {
        "metrics": [Commits(index, start, end),
                    Authors(index, start, end)]
    }

    return results