Fix @classproperty decorator (#1287)

Removed unnecessary `Self` hints on classproperty methods.

The removal of `self: Self` fixes #1285. Regressed in #1253.

django-stubs/utils/functional.pyi

@@ -91,10 +91,10 @@ def partition(
 _Get = TypeVar("_Get", covariant=True)
 
 class classproperty(Generic[_Get]):
-    fget: Callable[[Self], _Get] | None
-    def __init__(self: Self, method: Callable[[Self], _Get] | None = ...) -> None: ...
-    def __get__(self: Self, instance: Self | None, cls: type[Self] = ...) -> _Get: ...
-    def getter(self: Self, method: Callable[[Self], _Get]) -> classproperty[_Get]: ...
+    fget: Callable[[Any], _Get] | None
+    def __init__(self, method: Callable[[Any], _Get] | None = ...) -> None: ...
+    def __get__(self, instance: Any | None, cls: type[Any] = ...) -> _Get: ...
+    def getter(self, method: Callable[[Any], _Get]) -> classproperty[_Get]: ...
 
 class _Getter(Protocol[_Get]):
     """Type fake to declare some read-only properties (until `property` builtin is generic)

tests/typecheck/utils/test_functional.yml

@@ -49,3 +49,21 @@
 
       foo(s)                         # E: Argument 1 to "foo" has incompatible type "_StrPromise"; expected "str"
       bar(s)
+
+-   case: classproperty_usage
+    main: |
+      from typing import Any
+      from django.utils.functional import classproperty
+
+      class Foo:
+          @classproperty
+          def attr(cls: Any) -> str: ...
+
+          reveal_type(attr)      # N: Revealed type is "django.utils.functional.classproperty[builtins.str]"
+          reveal_type(attr.getter)  # N: Revealed type is "def (method: def (Any) -> builtins.str) -> django.utils.functional.classproperty[builtins.str]"
+
+      reveal_type(Foo.attr)      # N: Revealed type is "builtins.str"
+
+      class Bar(Foo):
+          def method(self) -> None:
+              reveal_type(self.attr)  # N: Revealed type is "builtins.str"