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: ['7041', 'A', 'x', 'Z', '9211', 'r', 'W', '4867', 'i', 'P', '6535', '1825', 'G', '5423', '1615', 'X', '3461', 'j', 'T', '509', 'o', 'U', 'I', '5669', '3139']

7041, 1, 24, 26, 9211, 18, 23, 4867, 9, 16, 6535, 1825, 7, 5423, 1615, 24, 3461, 10, 20, 509, 15, 21, 9, 5669, 3139