Definition: In this task, you are given an input list A. You need to convert all the alphabets in the list with a number representing their position in the English alphabet. E.g., replace A by 1, B by 2, a by 1, b by 2, and so on.
Input: ['O', '7189', 't', 'E', 'p', '2469', '5135', '3247', '4479', '4795', '4071', 'T', 'G', 'L', '5697', '3183', '8037', 'Z', 'd', 't', 'b', '1543', '6497', 'o', '4853', '8473', '2799', 'q', '517', '7701', '6197', 'T', '2515', '2223', '2069', '7473']

15, 7189, 20, 5, 16, 2469, 5135, 3247, 4479, 4795, 4071, 20, 7, 12, 5697, 3183, 8037, 26, 4, 20, 2, 1543, 6497, 15, 4853, 8473, 2799, 17, 517, 7701, 6197, 20, 2515, 2223, 2069, 7473