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: ['8871', '1297', 'W', 'f', 'Y', '8731', '113', '6707', '379', '9631', 'X', 'C', 'q']
Example Output: 35729

Example Input: ['9863', 'y']
Example Output: 9863

Example Input: ['4865', '8391', '2105', '2149', 'N', 'o', 'N', 'j', '3863', '5635', 'q', 'b']
Example Output:
27008