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: ['l', '2149', '3321', 'E', 'h', '7869', 'd', 'U', 'N', '8219', '6831', '1775', '4365', '9199', 'x', 'A', '2585', '6907', 'S', 'E', 'V', '197']

12, 2149, 3321, 5, 8, 7869, 4, 21, 14, 8219, 6831, 1775, 4365, 9199, 24, 1, 2585, 6907, 19, 5, 22, 197