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]: ['7755', '8383', 'y', 'k', '4869', '2809']
[A]: 23816


[Q]: ['4533', 'D', '823', 'a', 'x', 'p', '9787', '2587', 'T', 'Z', '2207', '8719', 'F', '7675', 'T', '2777', '203', 'N', 'o']
[A]: 39311


[Q]: ['U', '8873']
[A]:
8873