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: ['2237', '2597', '2593', 'Y', '5345', 'g', 'l', 'I', 'p', 'u', 'L', 'T', '617', '9759', 'b', 'w', '7097', '9863']

SOLUTION: 40108

PROBLEM: ['O', 'j', 'Z', 'u', '7427', '4225', '3139', '9993', '9945', '3639', 'h', 'j', 'f', '6511', 'e', '4607', '2741', '4743']

SOLUTION: 56970

PROBLEM: ['w', 'X', '7179', '8555', '4817', '8175', '4629', 'L', 'q', '1703', 'b', '2649']

SOLUTION:
37707