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: ['q', 'N', 'y', '7859', 'u', '2861', '4151', 'Q', 'x']

Answer: 14871


Question: ['4425', 'x', '1959', 'C', 'c', 'D', 'M', '8317', 'q', 'x', '4277', 'N', 'z', 'I', '1921', 'o', 't']

Answer: 20899


Question: ['4609', 'p', '5009', '8435', '9953', 'h', '4159', '3143', 'i']

Answer:
35308