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: ['4201', '6445', '4009', 'q']
Example Output: 14655

Example Input: ['6723', '1', '6357', '1497', 'A', 'p', 'N', 'T']
Example Output: 14578

Example Input: ['2543', 'd', 'R', '5911']
Example Output:
8454