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: ['2787', 'z', '9351', '3339']

Answer: 15477


Question: ['6849', 'I', 'p', 's', 'L', '4757', 'j', 'x', 'm', 'P', '5237', '1105', '9015', '9279', 'Q']

Answer: 36242


Question: ['8627', 'Y', '1407', '5303', 'A', 'X']

Answer:
15337