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: ['89', '5965', '9463', 'k']

Answer: 15517


Question: ['r', '3537', 'T', '3611', 'k', '4983', 'h', '4317', '8727', 'E', '6471', '8465', 'f', '5429', 'T', '2169', '2171', 'P', '6941', 'D']

Answer: 56821


Question: ['w', '5403', 'm', '4921', 'C', 'j', '9087', 'O', 'W']

Answer:
19411