fix: type lint check

Author: KunxiSun

sqlmodel/sql/sqltypes.py

@@ -1,10 +1,13 @@
-from typing import Any, cast, Optional
+from typing import Any, cast, Optional, TypeVar
 from enum import IntEnum as _IntEnum
 
 from sqlalchemy import types
 from sqlalchemy.engine.interfaces import Dialect
 
 
+_TIntEnum = TypeVar('_TIntEnum', bound="_IntEnum")
+
+
 class AutoString(types.TypeDecorator):  # type: ignore
     impl = types.String
     cache_ok = True
@@ -43,7 +46,7 @@ class IntEnum(types.TypeDecorator):  # type: ignore
 
     impl = types.Integer
 
-    def __init__(self, enum_type: _IntEnum, *args, **kwargs):
+    def __init__(self, enum_type: _TIntEnum, *args, **kwargs):
         super().__init__(*args, **kwargs)
 
         # validate the input enum type
@@ -54,15 +57,15 @@ def __init__(self, enum_type: _IntEnum, *args, **kwargs):
 
         self.enum_type = enum_type
 
-    def process_result_value(self, value: Optional[int], dialect) -> Optional[_IntEnum]:
+    def process_result_value(self, value: Optional[int], dialect: Dialect) -> Optional[_TIntEnum]:
 
         if value is None:
             return None
 
         result = self.enum_type(value)
         return result
 
-    def process_bind_param(self, value: Optional[_IntEnum], dialect) -> Optional[int]:
+    def process_bind_param(self, value: Optional[_TIntEnum], dialect: Dialect) -> Optional[int]:
 
         if value is None:
             return None