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:
['4975', 'M', 'C', 'D', 't', 'i', 't', 'L']
answer:
4975


question:
['D', 'C', '7295', 'g', 'j', '1387', 'O', '4701', 'B', 'd', 'W', 'b', 's', 'n', 'n', '4917', '2941', '1825', 'x']
answer:
23066


question:
['4949', '2459', 'n', 'f', 'n', 'v', '8421', '1519', '4859', 'c', '9923', '2829', 'K', '4937', 'W', 'R']
answer:

39896