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.

['6815', 'A', '1055', '4687', '8675', '4615', 'a', '2127', 'w', 'l', 'J', '5025', 'c', 't', '9727', 'G', '8431']
51157

['5715', 'r', 'R']
5715

['c', '7061', '3815', 'N', '5837', '6275', '3907', '8949', '6399', '1879', '5995', 'h', 'Y', '8329', 'q', 'n', 'n', '5061', 'a']

63507