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: ['3319', 'e', 'c', 'G', '2399', '1557', '4813', 'z', 'U', '4895', 's', '1193', 'A', 'G']

SOLUTION: 18176

PROBLEM: ['3557', '3345', '307', '9791', '1897', 'O']

SOLUTION: 18897

PROBLEM: ['u', 'R', 'I']

SOLUTION:
0