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]: ['J', '5149', 'H', 'L', 'm', 'h', '3863', 'n', 'z']
[EX A]: 9012

[EX Q]: ['r', 'B', '8791', '3165', 'n', 'm']
[EX A]: 11956

[EX Q]: ['2355', 'W', 's']
[EX A]:
2355