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: ['J', '5149', 'H', 'L', 'm', 'h', '3863', 'n', 'z']
Example Output: 9012

Example Input: ['5829', '9755', '67', 'F', '6347', 'p', 'i', 'X', 'z', 'o', '2321', 'F', '6145', 'B', '3903']
Example Output: 34367

Example Input: ['m', 'Z']
Example Output:
0