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: ['4861', 'k', 'f', '2993', 'G', 'F', 'Z', 'S', 'W', 'S', 'j', 'i', 'Z', 'z', 'H', 'd', '4819', 'v', 'l', '5357', 'W']

4861, 11, 6, 2993, 7, 6, 26, 19, 23, 19, 10, 9, 26, 26, 8, 4, 4819, 22, 12, 5357, 23