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: ['u', 'W', '1561', '9243', '4923', '9385']

SOLUTION: 25112

PROBLEM: ['8871', '1297', 'W', 'f', 'Y', '8731', '113', '6707', '379', '9631', 'X', 'C', 'q']

SOLUTION: 35729

PROBLEM: ['8759', 'f', 'U', '7865', 'S', 'q', '6141', 'd', '595', 'U', 's', '5277', '5939']

SOLUTION:
34576