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: ['3575', '8877', '3231', 'v', '9083', '317', 'M', '8975', 'x', 'F']

SOLUTION: 34058

PROBLEM: ['D', 'K', 'n', 'd', 'i', 'U']

SOLUTION: 0

PROBLEM: ['1035', 'Z', 'X', '9237', '6329', 'p', '4081', 'R', 'f', '2961', '5197', 'w', '5653', 'a']

SOLUTION:
34493