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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 download(self, days=60):
 """Downloaded OFX response for the given time range :param days: Number of days to look back at :type days: integer :rtype: :py:class:`StringIO` """

        days_ago = datetime.datetime.now() - datetime.timedelta(days=days)
        as_of = time.strftime("%Y%m%d", days_ago.timetuple())
        query = self._download_query(as_of=as_of)
        response = self.institution.client().post(query)
        return StringIO(response)