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]: ['3683', 'U', 'x', '313', 'n', '3837', '3299', '2081', '2773', 'r', 'O', '257', '6647', '585', 'o']
[EX A]: 23475

[EX Q]: ['9787', '1491', '4411', '5261', 'U', '9787', 'b']
[EX A]: 30737

[EX Q]: ['j', '6731', 'h', 'G', 'F', '6899', '4317', 'm', '9491', 'l', '971']
[EX A]:
28409