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.
Input: ['b', 'S', '3609', '9963', '8667', '3817', '7855', 'h', '8849', 'O', '8637', 'h', 'o', '9913', '9103', '4623', '7419', 'M', '2155', 'o', '8633', 'b', '2111', '1641', 'X', '7415', 't', 'F', 'R', '2501', 'H', 'Y', 'u', 'h', '9473']

2, 19, 3609, 9963, 8667, 3817, 7855, 8, 8849, 15, 8637, 8, 15, 9913, 9103, 4623, 7419, 13, 2155, 15, 8633, 2, 2111, 1641, 24, 7415, 20, 6, 18, 2501, 8, 25, 21, 8, 9473