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', '469', 'o', 'g', 'R', '6719', 'j', '7777', '3829']

6, 469, 15, 7, 18, 6719, 10, 7777, 3829