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: ['5499', '39', 'Q', 'b', 'W', '7155', '2515']

Answer: 15208


Question: ['2485', 'Q', 'G', '5533', 'Y', '21', 'D', 'S']

Answer: 8039


Question: ['7599', 'E', 'U', 'u', '3669', '4339', 'x', '4679', '5755']

Answer:
26041