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.
--------
Question: ['Y', '8169', '9067']

Answer: 17236


Question: ['l', 'V']

Answer: 0


Question: ['4271', '755', '2133', '9815', '9833', '4857', 'n', 'K', '6145', 'S', 'V', '6273', 'f', 'm', 'z']

Answer:
44082