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: ['387', '4143', 'N', 'm', '3577', '57', '5067', 'g', 'Q', 'f', 'J', '6799', 'W', 'v', 'x', '661', 'c', 'z', '2881', '1803', 'u', 'v', '3021', 'I', '1603', '3343', 'p', 'x', '3935', '6733', 'u', 'd', 'R', 'f', 'E']

387, 4143, 14, 13, 3577, 57, 5067, 7, 17, 6, 10, 6799, 23, 22, 24, 661, 3, 26, 2881, 1803, 21, 22, 3021, 9, 1603, 3343, 16, 24, 3935, 6733, 21, 4, 18, 6, 5