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: ['191', 'R', 'Q', '7809', '4851', 'b', 'e', 'H', 'E', 'I', 'r', 'A', 'g', 'e', 'g', 'I', 'j', 'f', '7287']

Answer: 20138


Question: ['b', '5689', '119', 'p', 'P', 'J', 'w', 'm', '7397', 'Y', '447', 'O', 'p', '319', 'H', 'U']

Answer: 13971


Question: ['6839', '7867', '4073', 'u']

Answer:
18779