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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(self, year, week, overwrite=False):
 """Fetch PageViews and Downloads from Elasticsearch."""

        self.config['overwrite_files'] = overwrite
        time_start = time.time()
        self._fetch_pageviews(self.storage, year, week, ip_users=False)
        self._fetch_downloads(self.storage, year, week, ip_users=False)
        # CDS has no user_agent before this date 1433400000:
        self._fetch_pageviews(self.storage, year, week, ip_users=True)
        self._fetch_downloads(self.storage, year, week, ip_users=True)
        logger.info('Fetch %s-%s in %s seconds.', year, week,
                    time.time() - time_start)