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: ['q', 'Y', '6021', '4045']

SOLUTION: 10066

PROBLEM: ['135', 'a', 'X', '8067', '8447', '4009', '4221', 'o', 'A', 'x']

SOLUTION: 24879

PROBLEM: ['B', '7843', '4313', '8033', 'e', '8449', '2311', '6783', 'D', 'z', 'T', '6135', 'l']

SOLUTION:
43867