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: ['G', 'e', 'R', '4427', '3401', '3065', 'I', '2781', '6829', '5261']
Example Output: 25764

Example Input: ['J', 'S', 'S', 'U', 'w', '7691', '7529', 'B', '3861', '4557', 'd', '569', '1547']
Example Output: 25754

Example Input: ['3319', 'e', 'c', 'G', '2399', '1557', '4813', 'z', 'U', '4895', 's', '1193', 'A', 'G']
Example Output:
18176