def _send_report(self, rcpts, subject):
        """send notification mail with some additional useful info"""
        stats = self.crawler.stats
        s = "Memory usage at engine startup : %dM\r\n" % (stats.get_value('memusage/startup')/1024/1024)
        s += "Maximum memory usage           : %dM\r\n" % (stats.get_value('memusage/max')/1024/1024)
        s += "Current memory usage           : %dM\r\n" % (self.get_virtual_size()/1024/1024)

        s += "ENGINE STATUS ------------------------------------------------------- \r\n"
        s += "\r\n"
        s += pformat(get_engine_status(self.crawler.engine))
        s += "\r\n"
        self.mail.send(rcpts, subject, s)
send notification mail with some additional useful info
stackoverflow/venv/lib/python3.6/site-packages/scrapy/extensions/memusage.py