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: ['R', '9751', '4367', 'l', 'N', '5125', '8751', '7507', 'y', 'K', '6127']

Answer: 41628


Question: ['4869', 'L']

Answer: 4869


Question: ['S', 'D', '3101', '4967', '8197', '5025', '4257', 'S', 'X', '7641', 'n', '6775', '4719', 'o', '2821', 'x', '5605', '2181']

Answer:
55289