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: ['h', 'a', '1645', '2391', '759', '519', '3331', '2831', '3427', '9893', 'u', 'J', '7391', '8379', 'V']

SOLUTION: 40566

PROBLEM: ['B', '9189', '3691', '2869', '1525', 'd', 'H', 'P', '8613', 'b', 'r', '5289', 'V', '6433', '8733', 'K', '8105', '1041', 'U', 'L']

SOLUTION: 55488

PROBLEM: ['j', '7919', '1295', '7125', '4855', '6883', 'd', 'B', 'z']

SOLUTION:
28077