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: ['D', '5207', 'E', '119', 'g', '2991', 'G', 'g', 'u']

Answer: 8317


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

Answer: 51583


Question: ['7913', '8521', '3717', 'Q', '3165', '5707', 'R', 'r', '3209', '7445', 'D']

Answer:
39677