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: ['1391', '1719', '8547', 'x', 'a', 'j', '6395', 't', '3421', '6607', 'M', '1645', 'H', 'x', 't']

Answer: 29725


Question: ['c', '4501', 'O']

Answer: 4501


Question: ['895', 'H', 'Z', '8545', '797', '1217', 'N', 'D', 'V', 'z', 'n', '1551', 'M', '2417', '6775']

Answer:
22197