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.

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

['9069', '8333', 'H', '2049', '8051', 'L', '2749', '8819', '2883', '9317', 'M', '6515']
57785

['G', 'h', '8647', '7635', 'h', 'x', 'R', '1677', 'k', 'c', '2331', '6277', 'v', 'b', '5971', '4901', 'w', '7437']

44876