Cleanup checks framework (#310)

django-stubs/core/checks/__init__.pyi

@@ -1,5 +1,17 @@
-from .messages import Warning as Warning, Info as Info, Debug as Debug, Error as Error, Critical as Critical
+from .messages import (
+    CheckMessage as CheckMessage,
+    Debug as Debug,
+    Info as Info,
+    Warning as Warning,
+    Error as Error,
+    Critical as Critical,
+    DEBUG as DEBUG,
+    INFO as INFO,
+    WARNING as WARNING,
+    ERROR as ERROR,
+    CRITICAL as CRITICAL,
+)
 
-from .registry import run_checks as run_checks, Tags as Tags, register as register
+from .registry import register as register, run_checks as run_checks, tag_exists as tag_exists, Tags as Tags
 
 from . import model_checks as model_checks

django-stubs/core/checks/messages.pyi

@@ -7,11 +7,11 @@ ERROR: int
 CRITICAL: int
 
 class CheckMessage:
-    level: Any = ...
-    msg: Any = ...
-    hint: Any = ...
+    level: int = ...
+    msg: str = ...
+    hint: Optional[str] = ...
     obj: Any = ...
-    id: Any = ...
+    id: Optional[str] = ...
     def __init__(
         self, level: int, msg: str, hint: Optional[str] = ..., obj: Any = ..., id: Optional[str] = ...
     ) -> None: ...
@@ -25,19 +25,9 @@ class Info(CheckMessage):
     def __init__(self, *args: Any, **kwargs: Any) -> None: ...
 
 class Warning(CheckMessage):
-    hint: str
-    id: str
-    level: int
-    msg: str
-    obj: Any
     def __init__(self, *args: Any, **kwargs: Any) -> None: ...
 
 class Error(CheckMessage):
-    hint: None
-    id: str
-    level: int
-    msg: str
-    obj: Any
     def __init__(self, *args: Any, **kwargs: Any) -> None: ...
 
 class Critical(CheckMessage):