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: ['h', '9539', '3373']
Example Output: 12912

Example Input: ['Q', '9787', '7533', '9489', 'C', '1753', '5121', '1405', '9267', '4815', 's', '5887']
Example Output: 55057

Example Input: ['1525', 'b', 'k', 'p', '6937', '2047', '1179', 'd', 'L', '687', '8019', '4689', 'v', 'A', 'T', '5791']
Example Output:
30874