In this task, you are given an input list A. You need to find all the elements of the list that are numbers and calculate their sum.

Example Input: ['4201', '6445', '4009', 'q']
Example Output: 14655

Example Input: ['3873', 'D', 'J', '2799', 'k', 'F', 'I', '3457', '5647', '4815', '7509', 'Y', '1251', '2211']
Example Output: 31562

Example Input: ['o', 'a', 'K', '6031']
Example Output:
6031