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.
['e', 'D', '8771', '3047', 'D', 'U', 'V', 'u', '7033', 'B', '6329', 'e', 'c', '221', '5203', 'E', '8099', 'P', 'Z', '4555']