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]: ['k', '6555', 'L', '7549', 'W', 'y', 'y', '8817', 'J', 't', 'X', 'M', 'N', 'G', '7441', '283']
[A]: 30645


[Q]: ['p', '4689']
[A]: 4689


[Q]: ['k', 'c']
[A]:
0