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: ['u', 'P', 'n', 'P', '537', '6431', 'u', 'Y']

SOLUTION: 21, 16, 14, 16, 537, 6431, 21, 25

PROBLEM: ['B', 'X', '5657', 'F', 'u', '6961', '5387', 'I', '6943', 'U', 'z', 'B', '8447', 'o', 'a', 'i', 'w', 'Q', 'h', 'h', 'T', 'g', '5161', '305']

SOLUTION: 2, 24, 5657, 6, 21, 6961, 5387, 9, 6943, 21, 26, 2, 8447, 15, 1, 9, 23, 17, 8, 8, 20, 7, 5161, 305

PROBLEM: ['L', 'g', 'i', 'k', '3885', '219', '5011', '5383', 'k', '2595', '9939', '5817', 'V', '3497', '4739', 'F', '7203', 'Q', '1899']

SOLUTION:
12, 7, 9, 11, 3885, 219, 5011, 5383, 11, 2595, 9939, 5817, 22, 3497, 4739, 6, 7203, 17, 1899