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: ['Y', '263', '641', '1163', 'p', 'r', 'L', '4425', 'C', '7585']
Example Output: 14077

Example Input: ['1671', 'H', '9271']
Example Output: 10942

Example Input: ['211', '7561', '8725', '6139', 'I', '6585', '4231', 't', '2983', 'T', 'S', '9569', 'R', 'b', 'N', 'X', '9009']
Example Output:
55013