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: ['T', '721', '6555', 'g', 'y', 'U', '3053', 'A', '9663']
Example Output: 19992

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

Example Input: ['7857', '9457', '2211', 'u']
Example Output:
19525