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: ['6289', '9021', 'P', 'd', 'N', 'J', 'N', 'F', 'Z', 'K', 'L', '4759', 'j', 'Q', 'c', '255', '3423', 'i', 'M', '2499', 'p', 'T', '5069', '3451']

6289, 9021, 16, 4, 14, 10, 14, 6, 26, 11, 12, 4759, 10, 17, 3, 255, 3423, 9, 13, 2499, 16, 20, 5069, 3451