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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 fetch_weeks(self, weeks, overwrite=False):
 """Fetch and cache the requested weeks."""

        esf = ElasticsearchFetcher(self.store, self.config)
        for year, week in weeks:
            print("Fetch {}-{}".format(year, week))
            esf.fetch(year, week, overwrite)