TYP: Use Self for type checking (remaining locations/)

Author: topper-123

pandas/core/base.py

@@ -12,7 +12,6 @@
     Hashable,
     Iterator,
     Literal,
-    TypeVar,
     cast,
     final,
     overload,
@@ -27,6 +26,7 @@
     DtypeObj,
     IndexLabel,
     NDFrameT,
+    Self,
     Shape,
     npt,
 )
@@ -92,8 +92,6 @@
     "duplicated": "IndexOpsMixin",
 }
 
-_T = TypeVar("_T", bound="IndexOpsMixin")
-
 
 class PandasObject(DirNamesMixin):
     """
@@ -286,7 +284,7 @@ def _values(self) -> ExtensionArray | np.ndarray:
         raise AbstractMethodError(self)
 
     @final
-    def transpose(self: _T, *args, **kwargs) -> _T:
+    def transpose(self, *args, **kwargs) -> Self:
         """
         Return the transpose, which is by definition self.
 

pandas/core/dtypes/base.py

@@ -17,6 +17,7 @@
 from pandas._libs.hashtable import object_hash
 from pandas._typing import (
     DtypeObj,
+    Self,
     Shape,
     npt,
     type_t,
@@ -227,9 +228,7 @@ def empty(self, shape: Shape) -> type_t[ExtensionArray]:
         return cls._empty(shape, dtype=self)
 
     @classmethod
-    def construct_from_string(
-        cls: type_t[ExtensionDtypeT], string: str
-    ) -> ExtensionDtypeT:
+    def construct_from_string(cls, string: str) -> Self:
         r"""
         Construct this type from a string.
 

pandas/core/indexing.py

@@ -6,7 +6,6 @@
     TYPE_CHECKING,
     Hashable,
     Sequence,
-    TypeVar,
     cast,
     final,
 )
@@ -20,6 +19,7 @@
 from pandas._typing import (
     Axis,
     AxisInt,
+    Self,
 )
 from pandas.compat import PYPY
 from pandas.errors import (
@@ -85,8 +85,6 @@
         Series,
     )
 
-_LocationIndexerT = TypeVar("_LocationIndexerT", bound="_LocationIndexer")
-
 # "null slice"
 _NS = slice(None, None)
 _one_ellipsis_message = "indexer may only contain one '...' entry"
@@ -669,9 +667,7 @@ class _LocationIndexer(NDFrameIndexerBase):
     _takeable: bool
 
     @final
-    def __call__(
-        self: _LocationIndexerT, axis: Axis | None = None
-    ) -> _LocationIndexerT:
+    def __call__(self, axis: Axis | None = None) -> Self:
         # we need to return a copy of ourselves
         new_self = type(self)(self.name, self.obj)