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: ['i', 'A', 'a']

SOLUTION: 0

PROBLEM: ['1395', '3605', '6001', 's', 'h', 'T', 'K', 'X', '9413', 'X', '5099', 'c', 'f', 't', 'S', 'f', '4651']

SOLUTION: 30164

PROBLEM: ['8513', '837', 'E', 'a', '9081', '3457', 'W']

SOLUTION:
21888