Use @overload typing for SpriteList.__getitem__

Author: pushfoo

arcade/sprite_list/sprite_list.py

@@ -24,7 +24,9 @@
     Union,
     Generic,
     Callable,
-    cast, Sized,
+    cast,
+    overload,
+    Sized
 )
 
 from arcade import (
@@ -249,6 +251,14 @@ def __iter__(self) -> Iterator[SpriteType]:
         """Return an iterable object of sprites."""
         return iter(self.sprite_list)
 
+    @overload
+    def __getitem__(self, i: int) -> SpriteType:
+        ...
+
+    @overload
+    def __getitem__(self, i: slice) -> List[SpriteType]:
+        ...
+
     def __getitem__(self, i):
         return self.sprite_list[i]