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]: ['8669', '9115', '2573', '9261']
[A]: 29618


[Q]: ['2087', '8171', 'c', 'd', 'a', '5621', 'n']
[A]: 15879


[Q]: ['4875', '9709', 'O', '6687', 'M', 'Z']
[A]:
21271