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]: ['6787', 'W', 'I', '4929', 'j', 'I', '3487', 'F', '3927', 'Q', 's', 'X', '9939', 'n']
[A]: 29069


[Q]: ['B', 'K', '9399', 't', '5541', 'w', '1939', '7841', 'q']
[A]: 24720


[Q]: ['3691', '9715', '7225', 'R', 'L', 'E', '7383', '3173', '4937', '6415', 'Q', '9915', 'N']
[A]:
52454