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

[EX Q]: ['7755', '8383', 'y', 'k', '4869', '2809']
[EX A]: 23816

[EX Q]: ['d', 'K', 'x', '1955', 'Y', 'V', '2279']
[EX A]:
4234