TASK 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.
PROBLEM: ['7471', 'k', '5537', '3569']

SOLUTION: 7471, 11, 5537, 3569

PROBLEM: ['x', '9709', '1533', 'w', 'M', 'z', '7459', '9617', '6763', '729', 'F', '8815', '363', '3349', '5129', 'L', 'L']

SOLUTION: 24, 9709, 1533, 23, 13, 26, 7459, 9617, 6763, 729, 6, 8815, 363, 3349, 5129, 12, 12

PROBLEM: ['R', 'Q', 'E', '2153', 'q', 'd', '4599', '4507', '7691', '9607', 'U', 'o', 'g', 'h', 'S', 'l', '8125', '4111', 'r', '57', '617', '971']

SOLUTION:
18, 17, 5, 2153, 17, 4, 4599, 4507, 7691, 9607, 21, 15, 7, 8, 19, 12, 8125, 4111, 18, 57, 617, 971