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: ['o', '7099', 'G', 'v', 'H', 'J', 'k', '1607', 'i', '9765', '2489', '8031']

SOLUTION: 28991

PROBLEM: ['r', 'b', 'G', 'H', '255', '6809', '5133', '1059', '4317', 'P', '7219', 'd', '805', 'G', '5243', '8305', '8509', 'o']

SOLUTION: 47654

PROBLEM: ['D', 'O', 'o', 'Z', 'k', '5705', '9', '2689', '9925', '9145', '9439', 'f', 'x', '2867', '6597', '9605', '5625', 'D']

SOLUTION:
61606