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: ['1457', '8137', 'R', '9881', '6455', 'k', 'p', '1237', '1019', '4099', 'v', '6185', 'l', 's', 't', 'r', '5757', '793', 'l', 'v', '3951', '9185', '9301', 'V', '2943', '8437', '2175', 'P', 'g', 'j', '3997']

1457, 8137, 18, 9881, 6455, 11, 16, 1237, 1019, 4099, 22, 6185, 12, 19, 20, 18, 5757, 793, 12, 22, 3951, 9185, 9301, 22, 2943, 8437, 2175, 16, 7, 10, 3997