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]: ['R', 'I', 'f', 'K', 'p', '8579', 'e', '1223', 'I', 'K', '8311', '2147', '4241', 'z', '6671', 'r']
[A]: 31172


[Q]: ['3433', '6955', 'Q', 'E', '3557', 'S', '2931', '9879', 'S', 'f', 'Q']
[A]: 26755


[Q]: ['V', 'L', 'Z', '2651', '7071', '2277', 'T', '8911', '3019', 'q', '1419', '1351', 'L', '1107', 'r', 'P', '4895', '3431', '1613']
[A]:
37745