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', 'm', 'P', '2433', '6731']
9164

['M', 'F', '4477', '1565', '4407', 'r', 'v', '7237', '83', '5243', 'O', 'z', 'W', '7703', 'Q', 'i', '9657', 'n']
40372

['8879', 'z', 'a', 'S', 'D', 'e', 'p', 'k', 'x', '89', 'T', 'E', 'l', '4493', '267', 'J', '4079']

17807