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: ['A', '9775', '5867', 'n', '1329', '5973']

SOLUTION: 22944

PROBLEM: ['8609', '8045', '2517', '3821', 'x', '3895', 't']

SOLUTION: 26887

PROBLEM: ['Q', 'B', 'f', 'w', 'o', '2095', 'r', '1905', 'b', 'J', 'P', 'P', '5725', '5993']

SOLUTION:
15718