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: ['l', 'B', 'Y', '7543', '5091', '1917']

A: 14551
****
Q: ['3331', '5791', 'r', 'Q', '2243', '8229']

A: 19594
****
Q: ['P', '6829', 'P', '8985', '825', 'z']

A:
16639
****