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: ['C', '9973', 'b', '693', 'y', 'H', 'C', 'P', 'b', 'J', 'f', 'T', '2317', 'O', '5755', '8201', 'p', 'y', '8721', 'i']
Example Output: 35660

Example Input: ['B', 'u', '9227', 'b', '8767']
Example Output: 17994

Example Input: ['7455', 'd', '93', '9467', '7391', '1693', '525', '9121', '4913', 'z', '4615', 'C', '4809', '927', '623', '3417', '323', 'W', '6809', '15']
Example Output:
62196