import std.typecheck as tc
import typing
OptionalString = str | None
print(tc.checktype("wow", OptionalString))
print(tc.checktype(None, OptionalString))
print(tc.checktype(0xDEADBEEF, OptionalString))
@tc.check_args
def a(a:int,b:str,c:typing.Any):...
a(1,"",1223)