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: ['z', 'T', 'Y', 's', 'j', '585', '7833', '2601', '8057', 'S', '7037', '5799', '4477', '5377', '6301', 'P', 'm', '9431', 'f']
Example Output: 57498

Example Input: ['K', '5815', 'E', 'c', '7379', '4995', 'w', 'B', 'j', '6227', 'B', '733', '1491', '3191', '9413', '2751', 'O', 'J', '6239', '3521']
Example Output: 51755

Example Input: ['Z', '2615', '1741']
Example Output:
4356