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]: ['y', 'p', '3553', '2155', 'b', 'R', 'j', 'V', 'U']
[EX A]: 5708

[EX Q]: ['n', 'G', '5059', '8343', '8673', 'P', 'N', '5485', '2279', '6121', 'i', 'U', '7277', '8701', 'A', 'b', 'Z', 'R', '6371', 'G']
[EX A]: 58309

[EX Q]: ['j', '1971', '9469', 'l', '7867', '6053', 'q', 's', '5555']
[EX A]:
30915