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: ['j', '6731', 'h', 'G', 'F', '6899', '4317', 'm', '9491', 'l', '971']

Answer: 28409


Question: ['8665', '6083', '9819', 'H', 'p', 'S', 'R', '4311', 'R', '7193']

Answer: 36071


Question: ['1189', '6489', '8085', '897', 'R', '1987']

Answer:
18647