The Imam says that these words are a concession for a fasting person to have cupping done. The words of Sayyiduna Abu Sa'id Khudri (may Allah be pleased with him) are those which have been added to the hadith, and these are not the words of the Prophet Muhammad (peace and blessings be upon him). Perhaps the narrator Ta'tamar narrated this hadith from his memory, so these words were included in the hadith of the Prophet Muhammad (peace and blessings be upon him), or while narrating the hadith, he said these words that Sayyiduna Abu Sa'id (may Allah be pleased with him) said that a concession was given to the fasting person to have cupping done. So the students may not have written the words "Sayyiduna Abu Sa'id (may Allah be pleased with him) said" properly, and thus these words were added to the hadith.