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.

[EX Q]: ['7771', 'g']
[EX A]: 7771

[EX Q]: ['Q', '8317', '8989']
[EX A]: 17306

[EX Q]: ['4881', 'B', 'L', '391', 'q', 'K', 'M']
[EX A]:
5272