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: ['f', 'K', '1713', 'U', 'L', '6877', '5943', '1329', '8259', '5805', 'p', '4089', '5385', 'Y', 'F', 'C', 'a', '5061', 's', 'k', '2563', 'a', '6917', 'r', 'b', 'E', 'p', 'D', '5519', '9817', 'u', 'v', 'f', '5609', 'u', '5663', '5551', 's', '8813', '4049']

6, 11, 1713, 21, 12, 6877, 5943, 1329, 8259, 5805, 16, 4089, 5385, 25, 6, 3, 1, 5061, 19, 11, 2563, 1, 6917, 18, 2, 5, 16, 4, 5519, 9817, 21, 22, 6, 5609, 21, 5663, 5551, 19, 8813, 4049