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: ['6723', '1', '6357', '1497', 'A', 'p', 'N', 'T']

SOLUTION: 14578

PROBLEM: ['u', 'W', '1561', '9243', '4923', '9385']

SOLUTION: 25112

PROBLEM: ['8865', 'F', 'P', '4595', '1861', 'p', 'd', '1357', 'U', 'T', 'l', 'f', '7023', 'A', '5899', 'Q', 'u']

SOLUTION:
29600