TASK DEFINITION: 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.
PROBLEM: ['6565', 'T', 'O', '2901', '5121', 'y', '9617', 't', '7825']

SOLUTION: 32029

PROBLEM: ['5947', 'n', '9431', '7629', '7643', 'N', '141', '2353', 'l', 'F', '9665', '9489', 'X', '4905', 'H', 'L', '985']

SOLUTION: 58188

PROBLEM: ['6369', 'X', '3533', '6957', '447']

SOLUTION:
17306