Moved definitions of K and V outside of TYPE_CHECKING condition

Author: JohanMabille

traitlets/traitlets.py

@@ -495,17 +495,15 @@ def instance_init(self, obj: t.Any) -> None:
 G = TypeVar("G")
 S = TypeVar("S")
 T = TypeVar("T")
-
+K = TypeVar("K", default=str)
+V = TypeVar("V", default=t.Any)
 
 # Self from typing extension doesn't work well with mypy https://github.com/python/mypy/pull/14041
 # see https://peps.python.org/pep-0673/#use-in-generic-classes
 # Self = t.TypeVar("Self", bound="TraitType[Any, Any]")
 if t.TYPE_CHECKING:
     from typing_extensions import Literal, Self
 
-    K = TypeVar("K", default=str)
-    V = TypeVar("V", default=t.Any)
-
 
 # We use a type for the getter (G) and setter (G) because we allow
 # for traits to cast (for instance CInt will use G=int, S=t.Any)