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: ['B', 'p', 'v', '735', 'j', 'f', 'U', '7621', '8569', '6677', '3533', 'W', 'p', 'H', '7259', '8397', 'i', 'i', 's', 'S', 'W', '9985', 'S', 'p', 'O', 'u', 'p', '1283']

2, 16, 22, 735, 10, 6, 21, 7621, 8569, 6677, 3533, 23, 16, 8, 7259, 8397, 9, 9, 19, 19, 23, 9985, 19, 16, 15, 21, 16, 1283