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.

['6321', 'M', 'd', '3673']
9994

['o', '8089', '2159', '943', '1255', 'w', 'Y', '3723', 'n', '7767', '2209', 'F', 'c', 'J', '5259', '4427', 'n', 'U']
35831

['k', 'D', '8949', 'G', 'B', 'N', 'V', '2813', '5339', '5397']

22498