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]: ['A', '771', 'Q', 'b', '9929', '4991', 'q', '9863', '4363', '5721', 'C', '991', 'j', 'r', 'Q', 'B', 'K']
[A]: 36629


[Q]: ['x', 'V', 'g', '5469', 'c', '7873', 'T', 'p', '8109', '5395', 'h', 'z', 'T', '9373']
[A]: 36219


[Q]: ['4853', 't', '2687']
[A]:
7540