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.

Q: ['t', '7469', 'Y', 'N', '8137']

A: 15606
****
Q: ['w', '1335', 'G', 'h', '6729', '1999', 'u', 'I', 'r', 'm', '4757', 'W', '3715', '701', '1999']

A: 21235
****
Q: ['5399', '229', '4125', 'U', 'j', '2541', '4457', 'X', '999', 'e', 'U', '6619', 'V', 'H', 'R', 'j', 'N', 'q', 'H', 'R']

A:
24369
****