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: ['1693', '9237', '7591', '1593', 'R', '6295', '9379']
Example Output: 35788

Example Input: ['K', '479', 'u', '3489', 'o', '9589', '7153', '7649', '123', 'a', 'A', '3951', '847', 'N', 'R', '947', '9243', 'G', 'a']
Example Output: 43470

Example Input: ['q', '8361', '8137', 'S', 'J', '8423', 'c', '4937', 'w', 'm', '8373', '8637']
Example Output:
46868