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: ['9787', '1491', '4411', '5261', 'U', '9787', 'b']

Answer: 30737


Question: ['f', 'H', 'U', 'l', 'n', 'q', '2701', '339', 'X', 'H', 'O', 'q', '2313']

Answer: 5353


Question: ['7403', '6363', 'q', '3707', 'l', '9669', '4239', '1219', 'c', '5377', 'V', '9753', '2869', '2721', 'g', 'y', 'p', 'X']

Answer:
53320