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: ['6165', 'x', 'u', 'n', 'V', 'B', '4039', 'l', '991', 'x', '335', '9011', 'K', '8725', 'a', '6291', 'j']

SOLUTION: 35557

PROBLEM: ['m', 'e', 'W', 'N', '4459', '693', '3765', '2641']

SOLUTION: 11558

PROBLEM: ['3557', '5439', 'l', 'H', 'W', 'p', 'L', '993', '487', 'K', 'j', 'a', '8671', '217', 'W', '261']

SOLUTION:
19625