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.

['339', 'h', 'd', '7449', 'e', 'u', '5055', '7029', '9009', 'G', 'U', '3', '441', '3273', 'K', '3827', '7069', 'x']
43494

['29', 'N', '5061', '7191', 'z', '8367']
20648

['4637', 'J', 'm', 'r', '9381', 'r']

14018