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]: ['6019', '1467', '3415', '7785']
[EX A]: 18686

[EX Q]: ['I', '7815']
[EX A]: 7815

[EX Q]: ['517', 'b', 'W', 'W', 'U', '8355', 'E', '1435', '231', 'j']
[EX A]:
10538