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: ['4685', 'q', 'O', 'o', '3453', 'o', 'Y', 'C', 'a', 'i', '7283', 'J', 'n', 'Q', 'i']
Example Output: 15421

Example Input: ['o', 'a', 'K', '6031']
Example Output: 6031

Example Input: ['p', '7709', 'P', '1039', '6171', '3865', '5643', 'S', '1323', '4537', '7097', '7039', 'L', '4701', '9729', 'c', 'W']
Example Output:
58853