Если вы хотите [17, 23, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]
rowsList = [17, 23]
rowsList.extend(range(13))
Предполагая, что вы хотите [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 17, 23]
rowsList = [17, 23]
tmpList = []
tmpList.extend(range(13))
rowsList[:0] = tmpList