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.
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Question: ['3629', '8785', '9537', '8479', '3523', 'c', 'C', '5093', '2405', 'y', '1145', '8987', 'f']

Answer: 51583


Question: ['r', '6537', '3001', '7879']

Answer: 17417


Question: ['p', '2733', '4497', '2181', '1807', '1851', 'O', '5187', 'u']

Answer:
18256