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: ['E', 'v', 'l', 'c', 'g', '3929', 'q', 'j']

Answer: 3929


Question: ['a', 'j', 'v', '619', 't', 'a', '5777', 'x', 'R', 'P', '8897', 'j']

Answer: 15293


Question: ['499', 'p']

Answer:
499