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: ['9007', 'S', '3987', '5735', 'c', '2143', '1953', '8771', 'h', 'Y', 'n', '8789', 'u', '7751', '1731', '6855', 'J', '6249', 'P', '3997', '7673', 'j', '9841', 'f', '7063', 'f', '4541', 'H']

9007, 19, 3987, 5735, 3, 2143, 1953, 8771, 8, 25, 14, 8789, 21, 7751, 1731, 6855, 10, 6249, 16, 3997, 7673, 10, 9841, 6, 7063, 6, 4541, 8