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: ['k', 'Z', 'r', 'K', 'b', 'X', 'A']
Example Output: 0

Example Input: ['m', 'e', 'W', 'N', '4459', '693', '3765', '2641']
Example Output: 11558

Example Input: ['9655', '355', 'Y', 'N', '1397', '2739', '8985', '1679', '7403', 'D', 'Z', '2301', 'C']
Example Output:
34514