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: ['X', 'u', 'B', '269', '9089', 'M', '5175', 'K']

SOLUTION: 14533

PROBLEM: ['q', '867', 'e', 'z']

SOLUTION: 867

PROBLEM: ['w', '4201', 'y', '7815', '5445', '8777', '8281', 'Y', 'l', 'U', '6129', '1901', 'f', 's', '225', 'l']

SOLUTION:
42774