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.

[Q]: ['Y', 'X', 'd', 'N', '1877', '2865', 'M', '1249', '9385', 'v', 'o', 'P', 'P', '6029']
[A]: 21405


[Q]: ['i', 'A', 'a']
[A]: 0


[Q]: ['t', '137', 'J', '5389']
[A]:
5526