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', '9979', '8723', '1131', 'i', 'p', 'M']
[A]: 19833


[Q]: ['5715', 'r', 'R']
[A]: 5715


[Q]: ['9401', '937', 'r', '5373', 'B', '1947']
[A]:
17658