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: ['29', 'N', '5061', '7191', 'z', '8367']

Answer: 20648


Question: ['u', 'e', 'P', 'D', '255', '2573', 'E', 'P', 's', '3725', '3391', 'I', '5323', '885']

Answer: 16152


Question: ['3965', 'N', 'K', 'M', 't']

Answer:
3965