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: ['5791', '2511', '1027', '4939', 'f', '7251', '1853', '1365', 'Q', '5913', '3831', 'l', 'B', 'a', 'O', 'M', 'f', 's', '9197', 'H', '651', 'I', '4171', 'U', 'g', '8883', '677', '3011', 'S', '7335', 'u', '5347', 'a', '2779']

5791, 2511, 1027, 4939, 6, 7251, 1853, 1365, 17, 5913, 3831, 12, 2, 1, 15, 13, 6, 19, 9197, 8, 651, 9, 4171, 21, 7, 8883, 677, 3011, 19, 7335, 21, 5347, 1, 2779