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]: ['D', 'P', '9951', '2897', 'V', 'C', 'B', 'H', 'c', 'h', '2843', 'a']
[A]: 15691


[Q]: ['2765', '6767', '7645']
[A]: 17177


[Q]: ['5825', 'H', 'Z', 'R', 'X', 'j', '3835']
[A]:
9660