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: ['6921', 'a', 'U', '2821', '2111', 'h', '3937', '3697', 'd', '6309', 'q', '7961', '5287', '5375', '2721', '4523', 'V', '8633', 'c', '7643']

SOLUTION: 67939

PROBLEM: ['597', 'i', 'd', '3201', 'u', '1111', '8563', 'c', 'E', '5983', '6293']

SOLUTION: 25748

PROBLEM: ['1845', 'G', '8863', '1313', '9775', 'w', '705', 'w']

SOLUTION:
22501