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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 iter_code_frequency(self, number=-1, etag=None):
 """Iterate over the code frequency per week. Returns a weekly aggregate of the number of additions and deletions pushed to this repository. :param int number: (optional), number of weeks to return. Default: -1 returns all weeks :param str etag: (optional), ETag from a previous request to the same endpoint :returns: generator of lists ``[seconds_from_epoch, additions, deletions]`` .. note:: All statistics methods may return a 202. On those occasions, you will not receive any objects. You should store your iterator and check the new ``last_status`` attribute. If it is a 202 you should wait before re-requesting. .. versionadded:: 0.7 """

        url = self._build_url('stats', 'code_frequency', base_url=self._api)
        return self._iter(int(number), url, list, etag=etag)