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: ['9989', 'B', 'E', '5181']

Answer: 15170


Question: ['3497', '761', '6157', 'J', 'n', '139', '9895', '2939', 'K', 'I', '2161', 'c', 'a', '485', '7959', 'i', '4753', '3305', 'G', '3475']

Answer: 45526


Question: ['M', '3109', 'q', '6711', '4701', '9819', 'd', 's', '3347', 'm', 'u', 'c', '8233', 'W', 'N', 'j', '3501', 'q']

Answer:
39421