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: ['o', 'J', 'B', '7765', '7781', '5513', '8721', 'u', '9557', 'C', 'A', '1281', '6565', 'H', '5559', '1695', '7577']

SOLUTION: 62014

PROBLEM: ['2691', '3861', '7087', '4661', '6527']

SOLUTION: 24827

PROBLEM: ['7111', '7139', 'N', 'Y', '2229', 'b', 'S', '2925', '7117', '4741', '4941', '3033', 'R', 'u', 'i', '5551', 'j', '5899', 'l']

SOLUTION:
50686