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: ['2105', 'h', '2769', '8309', '9003', 't', 'U', '1993', '2859', '3295', 't', 'T', '8943', '7385', '1667', 'd', '7453', 'D', 'A', 'd', 'J', 'h', 'V', 'F', 'x', 'f', '4003', '8121']

SOLUTION: 2105, 8, 2769, 8309, 9003, 20, 21, 1993, 2859, 3295, 20, 20, 8943, 7385, 1667, 4, 7453, 4, 1, 4, 10, 8, 22, 6, 24, 6, 4003, 8121

PROBLEM: ['r', 'z', '8645', '9053', '3629', '7689', '4465', '5281', 'Y', 'B']

SOLUTION: 18, 26, 8645, 9053, 3629, 7689, 4465, 5281, 25, 2

PROBLEM: ['a', '4715', 'X', '4649', '6995']

SOLUTION:
1, 4715, 24, 4649, 6995