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: ['E', 'X', 'C', 'v', '2803', 'g', 'b', '763']
Example Output: 3566

Example Input: ['9403', '2607', 'G', '7901', 'K', '7967', 'a', 'n', '1967', 'x', 'g', '1081']
Example Output: 30926

Example Input: ['4153', 'I', '5249', '263', '3103', '9873', 'D', '7813', 'v', '2689', '7091', '6059', '3245', 'g', 'b', 'f', 'o', 'o', 'V', 'A']
Example Output:
49538