🐛 Fix Enum handling in SQLAlchemy (#165)

Co-authored-by: Sebastián Ramírez <tiangolo@gmail.com>

sqlmodel/main.py

@@ -31,18 +31,9 @@ from pydantic.fields import ModelField, Undefined, UndefinedType
 from pydantic.main import ModelMetaclass, validate_model
 from pydantic.typing import ForwardRef, NoArgAnyCallable, resolve_annotations
 from pydantic.utils import ROOT_KEY, Representation
-from sqlalchemy import (
-    Boolean,
-    Column,
-    Date,
-    DateTime,
-    Float,
-    ForeignKey,
-    Integer,
-    Interval,
-    Numeric,
-    inspect,
-)
+from sqlalchemy import Boolean, Column, Date, DateTime
+from sqlalchemy import Enum as sa_Enum
+from sqlalchemy import Float, ForeignKey, Integer, Interval, Numeric, inspect
 from sqlalchemy.orm import RelationshipProperty, declared_attr, registry, relationship
 from sqlalchemy.orm.attributes import set_attribute
 from sqlalchemy.orm.decl_api import DeclarativeMeta
@@ -396,7 +387,7 @@ def get_sqlachemy_type(field: ModelField) -> Any:
     if issubclass(field.type_, time):
         return Time
     if issubclass(field.type_, Enum):
-        return Enum
+        return sa_Enum(field.type_)
     if issubclass(field.type_, bytes):
         return LargeBinary
     if issubclass(field.type_, Decimal):