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: ['7669', '3367', 'A', 'Z', '6173', '4391', 'f', 'S', '9657', '2631']

SOLUTION: 33888

PROBLEM: ['4811', 'Q', '2289', 'N', 'I', '7681', 'z', '8179', '3359', '5299', 'R', 'z', '8697', '5781', '4803', '2715', '6511', '1371']

SOLUTION: 61496

PROBLEM: ['2167', 'y', 'u', '1817', '4087', 'a', 's', 'E', '2091', '763']

SOLUTION:
10925