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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 _check_by_re(self, url_data, content):
 """ Finds urls by re. :param url_data: object for url storing :param content: file content """

        for link_re in self._link_res:
            for u in link_re.finditer(content):
                self._save_url(url_data, content, u.group(1), u.start(1))