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: ['2485', 'Q', 'G', '5533', 'Y', '21', 'D', 'S']

SOLUTION: 8039

PROBLEM: ['1867', '5301', 'x', '3867', '8707', '2429', 'K', '59', '6629', 'v', 'A', 'y', 'P', '3829', '1979', 'R', '8481', '5767', 'h', 'U']

SOLUTION: 48915

PROBLEM: ['C', 'R', '4967', 'E', '2103', 'o', 'T', '631', 'Z']

SOLUTION:
7701