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: ['A', 'V', 'j', 'A', '1215', '7509', '1863', '8855', 'S', 'B', 'S', '5507']

1, 22, 10, 1, 1215, 7509, 1863, 8855, 19, 2, 19, 5507