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: ['W', 'c', '7971', 'J', 'o']
Example Output: 7971

Example Input: ['e', 'T', 'O', 'q', '5511', 'G', 'm', 'E', '2153', 'O', '1139', '5097', 'n', '5653', 'v']
Example Output: 19553

Example Input: ['8071', '7077', '4585', '5469']
Example Output:
25202