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.

['P', '237', 'X', '8893', '7931', 'F', '8359', 'S', '6931', '6953', 'r']
39304

['6787', 'W', 'I', '4929', 'j', 'I', '3487', 'F', '3927', 'Q', 's', 'X', '9939', 'n']
29069

['S', '445', '8793', '5345', 'J', '6477', 'i', '3185', 'C']

24245