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


question:
['6469', '3027', 'Z', '3353', 'a', 'S', '3879', '8471', 'H', 'I', 'y', '2661', '9007', 'D']
answer:
36867


question:
['2921', '4491']
answer:

7412