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', '8035', 'J', '2671', '7509', '1573', '6915', '8569', '345', 'T', 'P', 's', '1341', '7823', '8671', 'm', 'Q', 's', 'N']
Example Output: 53452

Example Input: ['F', 'z', '1159', '345']
Example Output: 1504

Example Input: ['8207', 'H', 'm', '3087', 'l', 'I', '2343', '5079', 'Q', 'R', 'Z', 'w', 'R', '25', '489', 'y']
Example Output:
19230