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.

['3683', 'U', 'x', '313', 'n', '3837', '3299', '2081', '2773', 'r', 'O', '257', '6647', '585', 'o']
23475

['d', 'b', 'W', '3201', 'C', 'o', '5187', '9723', '8177', 'F', '6703', 'U', '1393', '1035', '3507', '5993', '3857', 'r', 'C', 'j']
48776

['l', '8853', '1815', 'M', 'N', '7271', '3201', '8257', '4233', 'L', '4233', '6005', 'n', 'K', '2403', '8945', '3631']

58847