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.
['d', 'U', 'A', '2283', 'F', '719', '1031', '843', '9397', '4259', '9361', '9665', 'k', '2037', '9283', '9883', 'h', 's', 'o', 'G']