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: ['6051', '5303', '1509', '2797', 'Z', '4777', '721', '8563', 'K', '63', '9115', 'd', '7305', '9743', '7409']

Answer: 63356


Question: ['6669', 'n', 't', 'N', 'x', '8153', 'W', 'v', 'B', '3181', 'y', 'e', '3491']

Answer: 21494


Question: ['6569', 'u', 'L', 'Q', '9249', '6933', 'H', 'U', 'W', 'k', '8379', '1713', 'z', '643']

Answer:
33486