diff --git a/CHANGELOG.md b/CHANGELOG.md
index 833c2dc..2e1a922 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,7 @@
 
 ### Fixed
 
+- Fix mypy errors when using tomlkit to modify toml document. ([#326](https://github.com/python-poetry/tomlkit/issues/326))
 - Fix the incompatiblity with 3.13 because of the `datetime.replace()` change. ([#333](https://github.com/python-poetry/tomlkit/issues/333))
 - Revert the change of parsing out-of-order tables. ([#347](https://github.com/python-poetry/tomlkit/issues/347))
 
diff --git a/tomlkit/items.py b/tomlkit/items.py
index 661e09c..452aec7 100644
--- a/tomlkit/items.py
+++ b/tomlkit/items.py
@@ -521,6 +521,17 @@ def __reduce__(self):
     def __reduce_ex__(self, protocol):
         return self.__class__, self._getstate(protocol)
 
+    # Leave it here to improve type hint for `tomlkit.parse`
+    # For example:
+    #   doc = tomlkit.parse(Path('pyproject.toml').read_text())
+    #   print(doc['tool']['poetry'])
+    def __getitem__(self, key) -> Any:
+        raise NotImplementedError()
+
+    # Improve type hint for document modify, ex: `doc['tool']['poetry']={}`
+    def __setitem__(self, key, value) -> None:
+        raise NotImplementedError()
+
 
 class Whitespace(Item):
     """