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: ['4509', '4165', '8651', '8057', 'a', '2241', 't', 'i', 'q', 'S', '5149', 'J', 'j', '1373', 'W', 'X', '235', 'm', '3225']

SOLUTION: 37605

PROBLEM: ['j', 'A', 'L', 'i', 'I', '3827', '8245', 'H', 'J', '8117', 'w', '4659', 'Y', 'x', 'K']

SOLUTION: 24848

PROBLEM: ['s', 'r', '6555', '4929', '4187']

SOLUTION:
15671