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: ['g', 'h', '9141', '7825', 'a', 'u', '2389', 'r', '9739', '8337', 'Z', 'Z', '6717']

SOLUTION: 44148

PROBLEM: ['u', 'B', '2509', 'U', 'R', '7497', '1897', '8697', 't', 'W', '1021', '7937', 'F', 'g', '6901', 'I', '2957']

SOLUTION: 39416

PROBLEM: ['M', 'k', '8287', 'p', 'u', '6743', '4551', 'V', 'y']

SOLUTION:
19581