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: ['x', '5259', 'T', 'L', 'C', 'H', '2493', 'u', '3851', '2439', 'U']
Example Output: 14042

Example Input: ['V', 'h', '5549', 'K', 's', '8337', 'Y', '497', 'z', 'T', '4467', '6333', 'M', '1573', 'y', 'O', '5499', 's', 't', '6205']
Example Output: 38460

Example Input: ['U', '919', '4267', '747', '2489', '1209', '405', '6921', '213']
Example Output:
17170