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: ['7867', '2157', '1791', 'r', '1889', '4037', 'X', '2511', 'D', '429', '9247', 't', '1255', 'c', 'd', '687', '2077', '8271', '1849', 'B', '1461', 'Y', 'z', '9291', '7251', '9027', 'h', 't', 'W', '8251', '9007']

7867, 2157, 1791, 18, 1889, 4037, 24, 2511, 4, 429, 9247, 20, 1255, 3, 4, 687, 2077, 8271, 1849, 2, 1461, 25, 26, 9291, 7251, 9027, 8, 20, 23, 8251, 9007