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.
--------
Question: ['7669', '3367', 'A', 'Z', '6173', '4391', 'f', 'S', '9657', '2631']

Answer: 33888


Question: ['C', 'v', '1353', 'e', 'x', 'A', 'D', '1243', '477', 'z', '3483', '5213', 'k', 'm', 'n']

Answer: 11769


Question: ['z', '735', '6331', 'b', '5141', 'Q', 'W', 'E', 'F', '2279', '5117', '7969', 's', '5745', 'g', '6457', 'r', 'r', '3999']

Answer:
43773