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.

['U', '1531', 't', '6929', 'P', '9619', 'G', 'g', '8511']
21, 1531, 20, 6929, 16, 9619, 7, 7, 8511

['6521', 'f', 'm', '1051', 'w', 'C', 'H', 'X', '7715', '5243', '3365', 'l', 'X', 'J', 'y', 'U', '4367', 'v', '8399', '1731', 'z']
6521, 6, 13, 1051, 23, 3, 8, 24, 7715, 5243, 3365, 12, 24, 10, 25, 21, 4367, 22, 8399, 1731, 26

['1273', '931', '8283', '79', 'M', '1367', 'I', '7985', 'p', 'M']

1273, 931, 8283, 79, 13, 1367, 9, 7985, 16, 13