Corrected type hints

Tests/test_file_mpo.py

@@ -85,7 +85,9 @@ def test_exif(test_file: str) -> None:
         im_reloaded = roundtrip(im_original, save_all=True, exif=im_original.getexif())
 
     for im in (im_original, im_reloaded):
+        assert isinstance(im, MpoImagePlugin.MpoImageFile)
         info = im._getexif()
+        assert info is not None
         assert info[272] == "Nintendo 3DS"
         assert info[296] == 2
         assert info[34665] == 188

src/PIL/JpegImagePlugin.py

@@ -468,7 +468,7 @@ def load_djpeg(self) -> None:
 
         self.tile = []
 
-    def _getexif(self) -> dict[str, Any] | None:
+    def _getexif(self) -> dict[int, Any] | None:
         return _getexif(self)
 
     def _read_dpi_from_exif(self) -> None:
@@ -504,7 +504,7 @@ def _getmp(self) -> dict[int, Any] | None:
         return _getmp(self)
 
 
-def _getexif(self: JpegImageFile) -> dict[str, Any] | None:
+def _getexif(self: JpegImageFile) -> dict[int, Any] | None:
     if "exif" not in self.info:
         return None
     return self.getexif()._get_merged_dict()

src/PIL/PngImagePlugin.py

@@ -1054,7 +1054,7 @@ def load_end(self) -> None:
                 self._prev_im.paste(updated, self.dispose_extent, mask)
                 self.im = self._prev_im
 
-    def _getexif(self) -> dict[str, Any] | None:
+    def _getexif(self) -> dict[int, Any] | None:
         if "exif" not in self.info:
             self.load()
         if "exif" not in self.info and "Raw profile type exif" not in self.info:

src/PIL/WebPImagePlugin.py

@@ -96,7 +96,7 @@ def _open(self) -> None:
         # Initialize seek state
         self._reset(reset=False)
 
-    def _getexif(self) -> dict[str, Any] | None:
+    def _getexif(self) -> dict[int, Any] | None:
         if "exif" not in self.info:
             return None
         return self.getexif()._get_merged_dict()