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: ['8285', 'T', 'j', 'z', '7815', 'f', 'L']

8285, 20, 10, 26, 7815, 6, 12