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: ['f', 'F', 'E', '2279', 'r', '6419', 'd', 'M', '3975', '3797', '9201', 'F', 'c', '4753', '959', 'v', '8963', '4007']
Example Output: 44353

Example Input: ['K', 'p', '97', 'R', '2999', 'u', '7307', '6033', '6431', 'm', 'T']
Example Output: 22867

Example Input: ['1253', 'L', 'I', 'D', '4273', '8471', 'g', 'C', 'l', '9139', 'b', 'M', '1901', 't', 'i']
Example Output:
25037