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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 logs(self):
 """ Return relevant who-did-what pairs from the bug history """

        for record in self.history:
            if (record["when"] >= self.options.since.date
                    and record["when"] < self.options.until.date):
                for change in record["changes"]:
                    yield record["who"], change