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: ['k', '4991', '7289', '4355', 'I', '8415', '5175', '5329', 'G', 'a', '7193', 't', '8821', 'j', '7239', '405', 'y', 'O', '9881', 'w']

SOLUTION: 69093

PROBLEM: ['1965', '8127', 'x', '4981', '8077', 'O', '467', '701', 'V', 'm', 'y', '5989', '123', 't', '4019', 'j', '1827', '8799']

SOLUTION: 45075

PROBLEM: ['7387', '5513', '4971', 'U', 'm', '2663', '1599', '7417', '6337', '3861']

SOLUTION:
39748