Fix typing in `pl.core.mixins.hparams_mixin` (#10800)

* fix typing in hparams mixin

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* unused import

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

pyproject.toml

@@ -60,7 +60,6 @@ module = [
     "pytorch_lightning.core.decorators",
     "pytorch_lightning.core.lightning",
     "pytorch_lightning.core.mixins.device_dtype_mixin",
-    "pytorch_lightning.core.mixins.hparams_mixin",
     "pytorch_lightning.core.saving",
     "pytorch_lightning.distributed.dist",
     "pytorch_lightning.loggers.base",

pytorch_lightning/core/mixins/hparams_mixin.py

@@ -15,7 +15,7 @@ import copy
 import inspect
 import types
 from argparse import Namespace
-from typing import MutableMapping, Optional, Sequence, Union
+from typing import Any, MutableMapping, Optional, Sequence, Union
 
 from pytorch_lightning.core.saving import ALLOWED_CONFIG_TYPES, PRIMITIVE_TYPES
 from pytorch_lightning.utilities import AttributeDict
@@ -32,7 +32,7 @@ class HyperparametersMixin:
 
     def save_hyperparameters(
         self,
-        *args,
+        *args: Any,
         ignore: Optional[Union[Sequence[str], str]] = None,
         frame: Optional[types.FrameType] = None,
         logger: bool = True,
@@ -101,7 +101,9 @@ class HyperparametersMixin:
         self._log_hyperparams = logger
         # the frame needs to be created in this file.
         if not frame:
-            frame = inspect.currentframe().f_back
+            current_frame = inspect.currentframe()
+            if current_frame:
+                frame = current_frame.f_back
         save_hyperparameters(self, *args, ignore=ignore, frame=frame)
 
     def _set_hparams(self, hp: Union[MutableMapping, Namespace, str]) -> None:
@@ -113,7 +115,7 @@ class HyperparametersMixin:
             self._hparams = hp
 
     @staticmethod
-    def _to_hparams_dict(hp: Union[MutableMapping, Namespace, str]):
+    def _to_hparams_dict(hp: Union[MutableMapping, Namespace, str]) -> Union[MutableMapping, AttributeDict]:
         if isinstance(hp, Namespace):
             hp = vars(hp)
         if isinstance(hp, dict):
@@ -125,12 +127,12 @@ class HyperparametersMixin:
         return hp
 
     @property
-    def hparams(self) -> Union[AttributeDict, dict, Namespace]:
+    def hparams(self) -> Union[AttributeDict, MutableMapping]:
         """The collection of hyperparameters saved with :meth:`save_hyperparameters`. It is mutable by the user.
         For the frozen set of initial hyperparameters, use :attr:`hparams_initial`.
 
         Returns:
-            Union[AttributeDict, dict, Namespace]: mutable hyperparameters dicionary
+            Mutable hyperparameters dicionary
         """
         if not hasattr(self, "_hparams"):
             self._hparams = AttributeDict()