matplotlib · QuLogic · Oct 30, 2025 · Jul 15, 2025 · Jul 15, 2025 · Jul 15, 2025
diff --git a/lib/matplotlib/__init__.pyi b/lib/matplotlib/__init__.pyi
@@ -39,6 +39,7 @@ import contextlib
 from packaging.version import Version
 
 from matplotlib._api import MatplotlibDeprecationWarning
+from matplotlib.typing import RcKeyType, RcGroupKeyType
 from typing import Any, Literal, NamedTuple, overload
 from matplotlib.typing import LogLevel
 
@@ -69,18 +70,18 @@ def get_cachedir() -> str: ...
 def get_data_path() -> str: ...
 def matplotlib_fname() -> str: ...
 
-class RcParams(dict[str, Any]):
+class RcParams(dict[RcKeyType, Any]):
     validate: dict[str, Callable]
     def __init__(self, *args, **kwargs) -> None: ...
-    def _set(self, key: str, val: Any) -> None: ...
-    def _get(self, key: str) -> Any: ...
+    def _set(self, key: RcKeyType, val: Any) -> None: ...
+    def _get(self, key: RcKeyType) -> Any: ...
 
     def _update_raw(self, other_params: dict | RcParams) -> None: ...
 
     def _ensure_has_backend(self) -> None: ...
-    def __setitem__(self, key: str, val: Any) -> None: ...
-    def __getitem__(self, key: str) -> Any: ...
-    def __iter__(self) -> Generator[str, None, None]: ...
+    def __setitem__(self, key: RcKeyType, val: Any) -> None: ...
+    def __getitem__(self, key: RcKeyType) -> Any: ...
+    def __iter__(self) -> Generator[RcKeyType, None, None]: ...
     def __len__(self) -> int: ...
     def find_all(self, pattern: str) -> RcParams: ...
     def copy(self) -> RcParams: ...
@@ -95,17 +96,17 @@ def rc_params_from_file(
 rcParamsDefault: RcParams
 rcParams: RcParams
 rcParamsOrig: RcParams
-defaultParams: dict[str, Any]
+defaultParams: dict[RcKeyType, Any]
 
-def rc(group: str, **kwargs) -> None: ...
+def rc(group: RcGroupKeyType, **kwargs) -> None: ...
 def rcdefaults() -> None: ...
 def rc_file_defaults() -> None: ...
 def rc_file(
     fname: str | Path | os.PathLike, *, use_default_template: bool = ...
 ) -> None: ...
 @contextlib.contextmanager
 def rc_context(
-    rc: dict[str, Any] | None = ..., fname: str | Path | os.PathLike | None = ...
+    rc: dict[RcKeyType, Any] | None = ..., fname: str | Path | os.PathLike | None = ...
 ) -> Generator[None, None, None]: ...
 def use(backend: str, *, force: bool = ...) -> None: ...
 @overload

diff --git a/lib/matplotlib/_mathtext.py b/lib/matplotlib/_mathtext.py
@@ -570,7 +570,7 @@ def __init__(self, default_font_prop: FontProperties, load_glyph_flags: LoadFlag
 
         super().__init__(default_font_prop, load_glyph_flags)
         for texfont in "cal rm tt it bf sf bfit".split():
-            prop = mpl.rcParams['mathtext.' + texfont]
+            prop = mpl.rcParams['mathtext.' + texfont]  # type: ignore[index]
             font = findfont(prop)
             self.fontmap[texfont] = font
         prop = FontProperties('cmex10')

diff --git a/lib/matplotlib/pyplot.py b/lib/matplotlib/pyplot.py
@@ -143,6 +143,8 @@
         MarkerType,
         MouseEventType,
         PickEventType,
+        RcGroupKeyType,
+        RcKeyType,
         ResizeEventType,
         LogLevel
     )
@@ -787,13 +789,13 @@ def pause(interval: float) -> None:
 
 
 @_copy_docstring_and_deprecators(matplotlib.rc)
-def rc(group: str, **kwargs) -> None:
+def rc(group: RcGroupKeyType, **kwargs) -> None:
     matplotlib.rc(group, **kwargs)
 
 
 @_copy_docstring_and_deprecators(matplotlib.rc_context)
 def rc_context(
-    rc: dict[str, Any] | None = None,
+    rc: dict[RcKeyType, Any] | None = None,
     fname: str | pathlib.Path | os.PathLike | None = None,
 ) -> AbstractContextManager[None]:
     return matplotlib.rc_context(rc, fname)