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:
['5715', 'r', 'R']
answer:
5715


question:
['A', '9775', '5867', 'n', '1329', '5973']
answer:
22944


question:
['Y', '5279', 'E']
answer:

5279