Revert "Temporarily revert changes to verify that the tests pass"

This reverts commit be1202a.

sqlmodel/main.py

@@ -585,10 +585,24 @@ def get_config(name: str) -> Any:
             setattr(new_cls, "__abstract__", True)  # noqa: B010
         return new_cls
 
-    # Temporarily revert changes to verify that the tests pass
-    # Override SQLAlchemy, allow both SQLAlchemy and plain Pydantic models
     def __init__(
         cls, classname: str, bases: Tuple[type, ...], dict_: Dict[str, Any], **kw: Any
+    ) -> None:
+        return cls.__do_init__(bases, dict_, kw)  # type: ignore
+
+    def sqlmodel_rebuild(cls) -> None:
+        reg = cls._sa_registry
+        # clear any exisiting mappers for the cls
+        managers = [m for m in reg._managers if m.class_ == cls]
+        for m in managers:
+            reg._dispose_manager_and_mapper(m)
+            del reg._managers[m]
+
+        return cls.__do_init__(cls.__bases__, cls.__dict__, {})  # type: ignore
+
+    # Override SQLAlchemy, allow both SQLAlchemy and plain Pydantic models
+    def __do_init__(
+        cls, classname: str, bases: Tuple[type, ...], dict_: Dict[str, Any], **kw: Any
     ) -> None:
         # Only one of the base classes (or the current one) should be a table model
         # this allows FastAPI cloning a SQLModel for the response_model without