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: ['R', 'C', 'S', 'x', '1529', 'r']

Answer: 1529


Question: ['v', '9511', 'f', 'q']

Answer: 9511


Question: ['4357', '4203', '6433', 'Q', 'x', 'i', '101', 'z']

Answer:
15094