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: ['8755', 'A', '2893', '6703']

Answer: 18351


Question: ['Q', '6383', 'P', '8455', '3881', '5821', 'e', 'v', '1421', 'Q', '6377', '3157', '6407', 'q']

Answer: 41902


Question: ['4433', '7587', 'R', '8999', 't', '5945', '4333', 'i', 'Q', '9623', 'a', '2171', 't', 'D']

Answer:
43091