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]: ['2915', '4443', 'Z', '3409', '1417', 'H', 'T', 'u', '3373', 'U', '115', 'R']
[A]: 15672


[Q]: ['Q', '9787', '7533', '9489', 'C', '1753', '5121', '1405', '9267', '4815', 's', '5887']
[A]: 55057


[Q]: ['3699', '5651', '6243', 'p', 'o', '5953', '1287', 'L']
[A]:
22833