diff --git a/stdlib/_bisect.pyi b/stdlib/_bisect.pyi
index 1e909c2a7..3ca863a2e 100644
--- a/stdlib/_bisect.pyi
+++ b/stdlib/_bisect.pyi
@@ -1,8 +1,35 @@
-from typing import MutableSequence, Optional, Sequence, TypeVar
+import sys
+from _typeshed import SupportsLessThan
+from typing import Callable, MutableSequence, Optional, Sequence, TypeVar
 
 _T = TypeVar("_T")
 
-def bisect_left(a: Sequence[_T], x: _T, lo: int = ..., hi: Optional[int] = ...) -> int: ...
-def bisect_right(a: Sequence[_T], x: _T, lo: int = ..., hi: Optional[int] = ...) -> int: ...
-def insort_left(a: MutableSequence[_T], x: _T, lo: int = ..., hi: Optional[int] = ...) -> None: ...
-def insort_right(a: MutableSequence[_T], x: _T, lo: int = ..., hi: Optional[int] = ...) -> None: ...
+if sys.version_info >= (3, 10):
+    def bisect_left(
+        a: Sequence[_T], x: _T, lo: int = ..., hi: Optional[int] = ..., *, key: Optional[Callable[[_T], SupportsLessThan]] = ...
+    ) -> int: ...
+    def bisect_right(
+        a: Sequence[_T], x: _T, lo: int = ..., hi: Optional[int] = ..., *, key: Optional[Callable[[_T], SupportsLessThan]] = ...
+    ) -> int: ...
+    def insort_left(
+        a: MutableSequence[_T],
+        x: _T,
+        lo: int = ...,
+        hi: Optional[int] = ...,
+        *,
+        key: Optional[Callable[[_T], SupportsLessThan]] = ...,
+    ) -> None: ...
+    def insort_right(
+        a: MutableSequence[_T],
+        x: _T,
+        lo: int = ...,
+        hi: Optional[int] = ...,
+        *,
+        key: Optional[Callable[[_T], SupportsLessThan]] = ...,
+    ) -> None: ...
+
+else:
+    def bisect_left(a: Sequence[_T], x: _T, lo: int = ..., hi: Optional[int] = ...) -> int: ...
+    def bisect_right(a: Sequence[_T], x: _T, lo: int = ..., hi: Optional[int] = ...) -> int: ...
+    def insort_left(a: MutableSequence[_T], x: _T, lo: int = ..., hi: Optional[int] = ...) -> None: ...
+    def insort_right(a: MutableSequence[_T], x: _T, lo: int = ..., hi: Optional[int] = ...) -> None: ...