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', 'a', 'K', '6031']

SOLUTION: 6031

PROBLEM: ['V', 'h', '5549', 'K', 's', '8337', 'Y', '497', 'z', 'T', '4467', '6333', 'M', '1573', 'y', 'O', '5499', 's', 't', '6205']

SOLUTION: 38460

PROBLEM: ['6713', 'C', '6989', '3977', 'i', 'A', '6343', 'I', '8133', '5827', 'o', 'N', 'K', 'j', '8581', '687', 'I', '6529', '6595', 'Z']

SOLUTION:
60374