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: ['h', '6937', 'U', 'f', 'S', 'm', '9699', 'E', '4559', 'p', 'Z', 'o', '6409', 's', '4537', '5135', '6901', '6489', '5833', 'l']
Example Output: 56499

Example Input: ['H', 'i', '8085', 'E', 'q']
Example Output: 8085

Example Input: ['1815', 'e', '5415', '8865', '7741', 'E', 'h', 'h', 'E', '6761', '4919', 'G', '1099', 'n', 'X', 'Q', 'h']
Example Output:
36615