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: ['5273', '5539', '993', '8787', 'r', '1413', '3931', 'z', 'g', 'c', 'D', '9909', 'a', 'V', '1657', '2823', 'e', 't', 't', 'b', '3771', '1177', 'f', '855']

SOLUTION: 5273, 5539, 993, 8787, 18, 1413, 3931, 26, 7, 3, 4, 9909, 1, 22, 1657, 2823, 5, 20, 20, 2, 3771, 1177, 6, 855

PROBLEM: ['3723', '9019', '1475', '229', '2961', '2131', 'B', '2245', 'o', '2299', 'R', '8165', 'v', 'Q', '501', 'L', '6203', 'y', 'r', 'u', '327', '617', 'z', '3843', 'D', '5647', 'Y', 'f', '4809']

SOLUTION: 3723, 9019, 1475, 229, 2961, 2131, 2, 2245, 15, 2299, 18, 8165, 22, 17, 501, 12, 6203, 25, 18, 21, 327, 617, 26, 3843, 4, 5647, 25, 6, 4809

PROBLEM: ['E', '5647', 'O', '3573', '2325', '8757', 'L', 'N', '3617', '9525', '5707', '1661', '2299', 'M']

SOLUTION:
5, 5647, 15, 3573, 2325, 8757, 12, 14, 3617, 9525, 5707, 1661, 2299, 13