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: ['7501', 'c', 'n', '3551', 'U', '8239', 'L', '3149', '9399', 'a', '2763', '2461', 'p']

SOLUTION: 7501, 3, 14, 3551, 21, 8239, 12, 3149, 9399, 1, 2763, 2461, 16

PROBLEM: ['8643', 'H', 'g', '7997', '4131', 'c', '7125', 'Z', '2811', '3543', '269', 'Y', 'E', 'R', 'A', '2241', 'G', '9967', '3141', 'B', 'Y', 'A', '3263', 'c', '251', 'D', 'z', '5509', '1805']

SOLUTION: 8643, 8, 7, 7997, 4131, 3, 7125, 26, 2811, 3543, 269, 25, 5, 18, 1, 2241, 7, 9967, 3141, 2, 25, 1, 3263, 3, 251, 4, 26, 5509, 1805

PROBLEM: ['6873', 'L', 'E', 'F', 'B', 'K', 'a', 'k', 'V', '8707', 'u', '2909', 'L', 'Q', 'E', '575', 'y', 'D', '9555', 'H', '519', 'a', '8009', '7977', '1933', '7775', '2365', 'R', '9007', '9199', 'n', 'r', 'X', '8857', '5377', '5455', 'u', 'm', 'H', '3457']

SOLUTION:
6873, 12, 5, 6, 2, 11, 1, 11, 22, 8707, 21, 2909, 12, 17, 5, 575, 25, 4, 9555, 8, 519, 1, 8009, 7977, 1933, 7775, 2365, 18, 9007, 9199, 14, 18, 24, 8857, 5377, 5455, 21, 13, 8, 3457