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]: ['8821', '7221']
[A]: 16042


[Q]: ['r', 'B', '8791', '3165', 'n', 'm']
[A]: 11956


[Q]: ['2917', 'N', '3059', 'q', 't', 'R', 'T', '6741']
[A]:
12717