fix: type hint with subscriptable types

mkdocs_rss_plugin/util.py

@@ -480,7 +480,7 @@ def get_description_or_abstract(
         else:
             return description if description else ""
 
-    def get_image(self, in_page: Page, base_url: str) -> Optional[tuple[str, str, int]]:
+    def get_image(self, in_page: Page, base_url: str) -> Optional[Tuple[str, str, int]]:
         """Get page's image from page meta or social cards and returns properties.
 
         Args:
@@ -489,7 +489,7 @@ def get_image(self, in_page: Page, base_url: str) -> Optional[tuple[str, str, in
                 with local path.
 
         Returns:
-            Optional[tuple[str, str, int]]: (image url, mime type, image length) or None if
+            Optional[Tuple[str, str, int]]: (image url, mime type, image length) or None if
                 there is no image set
         """
         if in_page.meta.get("image"):

setup.py

@@ -30,8 +30,8 @@ def load_requirements(requirements_files: Union[Path, List[Path]]) -> list:
     """Helper to load requirements list from a path or a list of paths.
 
     Args:
-        requirements_files (Path | list[Path]): path or list to paths of requirements
-            file(s)
+        requirements_files (Union[Path, List[Path]]): path or list to paths of
+            requirements file(s)
 
     Returns:
         list: list of requirements loaded from file(s)