Added strict type hints

src/PIL/Image.py

@@ -40,6 +40,7 @@
 from collections.abc import Callable, MutableMapping
 from enum import IntEnum
 from pathlib import Path
+from typing_extensions import Self
 
 try:
     from defusedxml import ElementTree
@@ -1181,7 +1182,7 @@ def quantize(
 
         return im
 
-    def copy(self):
+    def copy(self) -> Self:
         """
         Copies this image. Use this method if you wish to paste things
         into an image, but still retain the original.
@@ -2450,7 +2451,7 @@ def save(self, fp, format=None, **params):
         if open_fp:
             fp.close()
 
-    def seek(self, frame):
+    def seek(self, frame) -> Self:
         """
         Seeks to the given frame in this sequence file. If you seek
         beyond the end of the sequence, the method raises an
@@ -2537,7 +2538,7 @@ def getchannel(self, channel):
 
         return self._new(self.im.getband(channel))
 
-    def tell(self):
+    def tell(self) -> int:
         """
         Returns the current frame number. See :py:meth:`~PIL.Image.Image.seek`.
 

src/PIL/ImageSequence.py

@@ -17,6 +17,7 @@
 from __future__ import annotations
 
 from typing import Callable
+from typing_extensions import Self
 
 from . import Image
 
@@ -48,7 +49,7 @@ def __getitem__(self, ix: int) -> Image.Image:
             msg = "end of sequence"
             raise IndexError(msg) from e
 
-    def __iter__(self) -> Iterator:
+    def __iter__(self) -> Self:
         return self
 
     def __next__(self) -> Image.Image: