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: ['3839', 'D', '4741', 'L']

SOLUTION: 8580

PROBLEM: ['V', '8137', 'b', 'k', '2081', 'L', '9733', '7525', 'D', '2381', 'O']

SOLUTION: 29857

PROBLEM: ['A', 'W', 'T', 'D', 'l', 'N', 'Z', 'B', '8293', 'm', 'Z', 'J', 'v', '8931', '9621', '5561', '7835', '6019', '1479']

SOLUTION:
47739