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: ['8109', '5635', 'u', 'M', '1009']

SOLUTION: 14753

PROBLEM: ['5829', '9755', '67', 'F', '6347', 'p', 'i', 'X', 'z', 'o', '2321', 'F', '6145', 'B', '3903']

SOLUTION: 34367

PROBLEM: ['8957', '3635', '8375', 'W', 'Z', 'R', 'b', '6923', '7511']

SOLUTION:
35401