instruction:
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.
question:
['2787', '6085', '6989']
answer:
15861


question:
['W', '4453', '5895', 'Z', 'A', '7663', '2749', 'f', 'H', '6917', '1215', 'M', '1775', '5397', 'l', '8197', '5209', '8229', 'U']
answer:
57699


question:
['7607', 'I', '1427', '8463', '7487', 'H', '953', 'B', 'y', 'V', 'd', '4083', 'V', 'm', 'y', '9155', '2655', '8841', 'L', 'c']
answer:

50671