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:
['d', '7305', '8903', 'b', '7687', '6393', '6939']
answer:
37227


question:
['c', 'd']
answer:
0


question:
['4701', 'b', 'i', 'B', 'z', '7837', 'W']
answer:

12538