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: ['7411', 'Y', 'x', 'l', '4119', '7241']

SOLUTION: 18771

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

SOLUTION: 42558

PROBLEM: ['C', '1849', '6855', 'd', 'H', '7065', '4941', '9131', 'w', '7755']

SOLUTION:
37596