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: ['Q', '9787', '7533', '9489', 'C', '1753', '5121', '1405', '9267', '4815', 's', '5887']

Answer: 55057


Question: ['2729', 'W', 'i', '9073', '343', 'j', '2329', '9159', '4825']

Answer: 28458


Question: ['9509', 'd', 'J', '1697', '9113', '1053', '419']

Answer:
21791