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.
--------
Question: ['Y', '8169', '9067']

Answer: 17236


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

Answer: 1529


Question: ['8501', 'f', 'Z', '2399', 'd', '9837', 'Y', 'c', 'd', 'c', 'f', 'I', '9401', '2691', 'I', 'V', '2725', '6691', '189', '9865']

Answer:
52299