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: ['D', '7557', '2965', 'N', 'd', 'R', '2845', 'f', '8165', 'Y', 'N', '4109', 't', '7323']

4, 7557, 2965, 14, 4, 18, 2845, 6, 8165, 25, 14, 4109, 20, 7323