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: ['w', '7301', '9411', 'z', 'g', 'X', '1045', 'l', 'F', 'M', 'R', '7957', 'e', '5145']

SOLUTION: 30859

PROBLEM: ['6347', '5495', '169', '9503', 'H', '571', '6105', 'X', 'r', 'e', '7369', 'a', 'd', '6999']

SOLUTION: 42558

PROBLEM: ['l', 'E', '9637', 'c', 'W', '4907', '6953', 'K']

SOLUTION:
21497