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.

Example Input: ['g', 'A', 'r', '539', '5459', '2725', '7447', '3693', '1757', 'r', 'W', '5949', '4569', '5153', '3985', 'Q', '505', 'M', '8989']
Example Output: 50770

Example Input: ['433', 'y', '2015', '5997', 'X', 'u', '9321', '8037', 'N', 'Z', 'E', '4645', '627', '6595', '7679']
Example Output: 45349

Example Input: ['8697', 'O', 'm', 'g', 's', 'Q', 'G', 'p']
Example Output:
8697