diff --git a/docs_src/tutorial/many_to_many/tutorial003.py b/docs_src/tutorial/many_to_many/tutorial003.py
index 1e03c4af8..cec6e5656 100644
--- a/docs_src/tutorial/many_to_many/tutorial003.py
+++ b/docs_src/tutorial/many_to_many/tutorial003.py
@@ -3,25 +3,12 @@
 from sqlmodel import Field, Relationship, Session, SQLModel, create_engine, select
 
 
-class HeroTeamLink(SQLModel, table=True):
-    team_id: Optional[int] = Field(
-        default=None, foreign_key="team.id", primary_key=True
-    )
-    hero_id: Optional[int] = Field(
-        default=None, foreign_key="hero.id", primary_key=True
-    )
-    is_training: bool = False
-
-    team: "Team" = Relationship(back_populates="hero_links")
-    hero: "Hero" = Relationship(back_populates="team_links")
-
-
 class Team(SQLModel, table=True):
     id: Optional[int] = Field(default=None, primary_key=True)
     name: str = Field(index=True)
     headquarters: str
 
-    hero_links: List[HeroTeamLink] = Relationship(back_populates="team")
+    hero_links: List["HeroTeamLink"] = Relationship(back_populates="team")
 
 
 class Hero(SQLModel, table=True):
@@ -30,7 +17,20 @@ class Hero(SQLModel, table=True):
     secret_name: str
     age: Optional[int] = Field(default=None, index=True)
 
-    team_links: List[HeroTeamLink] = Relationship(back_populates="hero")
+    team_links: List["HeroTeamLink"] = Relationship(back_populates="hero")
+
+
+class HeroTeamLink(SQLModel, table=True):
+    team_id: Optional[int] = Field(
+        default=None, foreign_key="team.id", primary_key=True
+    )
+    hero_id: Optional[int] = Field(
+        default=None, foreign_key="hero.id", primary_key=True
+    )
+    is_training: bool = False
+
+    team: "Team" = Relationship(back_populates="hero_links")
+    hero: "Hero" = Relationship(back_populates="team_links")
 
 
 sqlite_file_name = "database.db"
diff --git a/docs_src/tutorial/relationship_attributes/back_populates/tutorial003.py b/docs_src/tutorial/relationship_attributes/back_populates/tutorial003.py
index 98e197002..8d91a0bc2 100644
--- a/docs_src/tutorial/relationship_attributes/back_populates/tutorial003.py
+++ b/docs_src/tutorial/relationship_attributes/back_populates/tutorial003.py
@@ -3,6 +3,21 @@
 from sqlmodel import Field, Relationship, SQLModel, create_engine
 
 
+class Hero(SQLModel, table=True):
+    id: Optional[int] = Field(default=None, primary_key=True)
+    name: str = Field(index=True)
+    secret_name: str
+    age: Optional[int] = Field(default=None, index=True)
+
+    team_id: Optional[int] = Field(default=None, foreign_key="team.id")
+    team: Optional["Team"] = Relationship(back_populates="heroes")
+
+    weapon_id: Optional[int] = Field(default=None, foreign_key="weapon.id")
+    weapon: Optional["Weapon"] = Relationship(back_populates="hero")
+
+    powers: List["Power"] = Relationship(back_populates="hero")
+
+
 class Weapon(SQLModel, table=True):
     id: Optional[int] = Field(default=None, primary_key=True)
     name: str = Field(index=True)
@@ -26,21 +41,6 @@ class Team(SQLModel, table=True):
     heroes: List["Hero"] = Relationship(back_populates="team")
 
 
-class Hero(SQLModel, table=True):
-    id: Optional[int] = Field(default=None, primary_key=True)
-    name: str = Field(index=True)
-    secret_name: str
-    age: Optional[int] = Field(default=None, index=True)
-
-    team_id: Optional[int] = Field(default=None, foreign_key="team.id")
-    team: Optional[Team] = Relationship(back_populates="heroes")
-
-    weapon_id: Optional[int] = Field(default=None, foreign_key="weapon.id")
-    weapon: Optional[Weapon] = Relationship(back_populates="hero")
-
-    powers: List[Power] = Relationship(back_populates="hero")
-
-
 sqlite_file_name = "database.db"
 sqlite_url = f"sqlite:///{sqlite_file_name}"
 
diff --git a/sqlmodel/__init__.py b/sqlmodel/__init__.py
index 495ac9c8a..af3742175 100644
--- a/sqlmodel/__init__.py
+++ b/sqlmodel/__init__.py
@@ -21,7 +21,6 @@
 from sqlalchemy.schema import PrimaryKeyConstraint as PrimaryKeyConstraint
 from sqlalchemy.schema import Sequence as Sequence
 from sqlalchemy.schema import Table as Table
-from sqlalchemy.schema import ThreadLocalMetaData as ThreadLocalMetaData
 from sqlalchemy.schema import UniqueConstraint as UniqueConstraint
 from sqlalchemy.sql import LABEL_STYLE_DEFAULT as LABEL_STYLE_DEFAULT
 from sqlalchemy.sql import (
@@ -71,7 +70,6 @@
 from sqlalchemy.sql import outerjoin as outerjoin
 from sqlalchemy.sql import outparam as outparam
 from sqlalchemy.sql import over as over
-from sqlalchemy.sql import subquery as subquery
 from sqlalchemy.sql import table as table
 from sqlalchemy.sql import tablesample as tablesample
 from sqlalchemy.sql import text as text
diff --git a/sqlmodel/main.py b/sqlmodel/main.py
index 2b69dd2a7..e06b651cf 100644
--- a/sqlmodel/main.py
+++ b/sqlmodel/main.py
@@ -642,6 +642,7 @@ class SQLModel(BaseModel, metaclass=SQLModelMetaclass, registry=default_registry
     __sqlmodel_relationships__: ClassVar[Dict[str, RelationshipProperty]]  # type: ignore
     __name__: ClassVar[str]
     metadata: ClassVar[MetaData]
+    __allow_unmapped__ = True # https://docs.sqlalchemy.org/en/20/changelog/migration_20.html#migration-20-step-six
 
     class Config:
         orm_mode = True
diff --git a/sqlmodel/sql/expression.py b/sqlmodel/sql/expression.py
index 264e39cba..29e7524ce 100644
--- a/sqlmodel/sql/expression.py
+++ b/sqlmodel/sql/expression.py
@@ -117,12 +117,12 @@ class SelectOfScalar(_Select, Generic[_TSelect]):
 
 
 @overload
-def select(entity_0: _TScalar_0, **kw: Any) -> SelectOfScalar[_TScalar_0]:  # type: ignore
+def select(entity_0: _TScalar_0) -> SelectOfScalar[_TScalar_0]:  # type: ignore
     ...
 
 
 @overload
-def select(entity_0: Type[_TModel_0], **kw: Any) -> SelectOfScalar[_TModel_0]:  # type: ignore
+def select(entity_0: Type[_TModel_0]) -> SelectOfScalar[_TModel_0]:  # type: ignore
     ...
 
 
@@ -133,7 +133,6 @@ def select(entity_0: Type[_TModel_0], **kw: Any) -> SelectOfScalar[_TModel_0]:
 def select(  # type: ignore
     entity_0: _TScalar_0,
     entity_1: _TScalar_1,
-    **kw: Any,
 ) -> Select[Tuple[_TScalar_0, _TScalar_1]]:
     ...
 
@@ -142,7 +141,6 @@ def select(  # type: ignore
 def select(  # type: ignore
     entity_0: _TScalar_0,
     entity_1: Type[_TModel_1],
-    **kw: Any,
 ) -> Select[Tuple[_TScalar_0, _TModel_1]]:
     ...
 
@@ -151,7 +149,6 @@ def select(  # type: ignore
 def select(  # type: ignore
     entity_0: Type[_TModel_0],
     entity_1: _TScalar_1,
-    **kw: Any,
 ) -> Select[Tuple[_TModel_0, _TScalar_1]]:
     ...
 
@@ -160,7 +157,6 @@ def select(  # type: ignore
 def select(  # type: ignore
     entity_0: Type[_TModel_0],
     entity_1: Type[_TModel_1],
-    **kw: Any,
 ) -> Select[Tuple[_TModel_0, _TModel_1]]:
     ...
 
@@ -170,7 +166,6 @@ def select(  # type: ignore
     entity_0: _TScalar_0,
     entity_1: _TScalar_1,
     entity_2: _TScalar_2,
-    **kw: Any,
 ) -> Select[Tuple[_TScalar_0, _TScalar_1, _TScalar_2]]:
     ...
 
@@ -180,7 +175,6 @@ def select(  # type: ignore
     entity_0: _TScalar_0,
     entity_1: _TScalar_1,
     entity_2: Type[_TModel_2],
-    **kw: Any,
 ) -> Select[Tuple[_TScalar_0, _TScalar_1, _TModel_2]]:
     ...
 
@@ -190,7 +184,6 @@ def select(  # type: ignore
     entity_0: _TScalar_0,
     entity_1: Type[_TModel_1],
     entity_2: _TScalar_2,
-    **kw: Any,
 ) -> Select[Tuple[_TScalar_0, _TModel_1, _TScalar_2]]:
     ...
 
@@ -200,7 +193,6 @@ def select(  # type: ignore
     entity_0: _TScalar_0,
     entity_1: Type[_TModel_1],
     entity_2: Type[_TModel_2],
-    **kw: Any,
 ) -> Select[Tuple[_TScalar_0, _TModel_1, _TModel_2]]:
     ...
 
@@ -210,7 +202,6 @@ def select(  # type: ignore
     entity_0: Type[_TModel_0],
     entity_1: _TScalar_1,
     entity_2: _TScalar_2,
-    **kw: Any,
 ) -> Select[Tuple[_TModel_0, _TScalar_1, _TScalar_2]]:
     ...
 
@@ -220,7 +211,6 @@ def select(  # type: ignore
     entity_0: Type[_TModel_0],
     entity_1: _TScalar_1,
     entity_2: Type[_TModel_2],
-    **kw: Any,
 ) -> Select[Tuple[_TModel_0, _TScalar_1, _TModel_2]]:
     ...
 
@@ -230,7 +220,6 @@ def select(  # type: ignore
     entity_0: Type[_TModel_0],
     entity_1: Type[_TModel_1],
     entity_2: _TScalar_2,
-    **kw: Any,
 ) -> Select[Tuple[_TModel_0, _TModel_1, _TScalar_2]]:
     ...
 
@@ -240,7 +229,6 @@ def select(  # type: ignore
     entity_0: Type[_TModel_0],
     entity_1: Type[_TModel_1],
     entity_2: Type[_TModel_2],
-    **kw: Any,
 ) -> Select[Tuple[_TModel_0, _TModel_1, _TModel_2]]:
     ...
 
@@ -251,7 +239,6 @@ def select(  # type: ignore
     entity_1: _TScalar_1,
     entity_2: _TScalar_2,
     entity_3: _TScalar_3,
-    **kw: Any,
 ) -> Select[Tuple[_TScalar_0, _TScalar_1, _TScalar_2, _TScalar_3]]:
     ...
 
@@ -262,7 +249,6 @@ def select(  # type: ignore
     entity_1: _TScalar_1,
     entity_2: _TScalar_2,
     entity_3: Type[_TModel_3],
-    **kw: Any,
 ) -> Select[Tuple[_TScalar_0, _TScalar_1, _TScalar_2, _TModel_3]]:
     ...
 
@@ -273,7 +259,6 @@ def select(  # type: ignore
     entity_1: _TScalar_1,
     entity_2: Type[_TModel_2],
     entity_3: _TScalar_3,
-    **kw: Any,
 ) -> Select[Tuple[_TScalar_0, _TScalar_1, _TModel_2, _TScalar_3]]:
     ...
 
@@ -284,7 +269,6 @@ def select(  # type: ignore
     entity_1: _TScalar_1,
     entity_2: Type[_TModel_2],
     entity_3: Type[_TModel_3],
-    **kw: Any,
 ) -> Select[Tuple[_TScalar_0, _TScalar_1, _TModel_2, _TModel_3]]:
     ...
 
@@ -295,7 +279,6 @@ def select(  # type: ignore
     entity_1: Type[_TModel_1],
     entity_2: _TScalar_2,
     entity_3: _TScalar_3,
-    **kw: Any,
 ) -> Select[Tuple[_TScalar_0, _TModel_1, _TScalar_2, _TScalar_3]]:
     ...
 
@@ -306,7 +289,6 @@ def select(  # type: ignore
     entity_1: Type[_TModel_1],
     entity_2: _TScalar_2,
     entity_3: Type[_TModel_3],
-    **kw: Any,
 ) -> Select[Tuple[_TScalar_0, _TModel_1, _TScalar_2, _TModel_3]]:
     ...
 
@@ -317,7 +299,6 @@ def select(  # type: ignore
     entity_1: Type[_TModel_1],
     entity_2: Type[_TModel_2],
     entity_3: _TScalar_3,
-    **kw: Any,
 ) -> Select[Tuple[_TScalar_0, _TModel_1, _TModel_2, _TScalar_3]]:
     ...
 
@@ -328,7 +309,6 @@ def select(  # type: ignore
     entity_1: Type[_TModel_1],
     entity_2: Type[_TModel_2],
     entity_3: Type[_TModel_3],
-    **kw: Any,
 ) -> Select[Tuple[_TScalar_0, _TModel_1, _TModel_2, _TModel_3]]:
     ...
 
@@ -339,7 +319,6 @@ def select(  # type: ignore
     entity_1: _TScalar_1,
     entity_2: _TScalar_2,
     entity_3: _TScalar_3,
-    **kw: Any,
 ) -> Select[Tuple[_TModel_0, _TScalar_1, _TScalar_2, _TScalar_3]]:
     ...
 
@@ -350,7 +329,6 @@ def select(  # type: ignore
     entity_1: _TScalar_1,
     entity_2: _TScalar_2,
     entity_3: Type[_TModel_3],
-    **kw: Any,
 ) -> Select[Tuple[_TModel_0, _TScalar_1, _TScalar_2, _TModel_3]]:
     ...
 
@@ -361,7 +339,6 @@ def select(  # type: ignore
     entity_1: _TScalar_1,
     entity_2: Type[_TModel_2],
     entity_3: _TScalar_3,
-    **kw: Any,
 ) -> Select[Tuple[_TModel_0, _TScalar_1, _TModel_2, _TScalar_3]]:
     ...
 
@@ -372,7 +349,6 @@ def select(  # type: ignore
     entity_1: _TScalar_1,
     entity_2: Type[_TModel_2],
     entity_3: Type[_TModel_3],
-    **kw: Any,
 ) -> Select[Tuple[_TModel_0, _TScalar_1, _TModel_2, _TModel_3]]:
     ...
 
@@ -383,7 +359,6 @@ def select(  # type: ignore
     entity_1: Type[_TModel_1],
     entity_2: _TScalar_2,
     entity_3: _TScalar_3,
-    **kw: Any,
 ) -> Select[Tuple[_TModel_0, _TModel_1, _TScalar_2, _TScalar_3]]:
     ...
 
@@ -394,7 +369,6 @@ def select(  # type: ignore
     entity_1: Type[_TModel_1],
     entity_2: _TScalar_2,
     entity_3: Type[_TModel_3],
-    **kw: Any,
 ) -> Select[Tuple[_TModel_0, _TModel_1, _TScalar_2, _TModel_3]]:
     ...
 
@@ -405,7 +379,6 @@ def select(  # type: ignore
     entity_1: Type[_TModel_1],
     entity_2: Type[_TModel_2],
     entity_3: _TScalar_3,
-    **kw: Any,
 ) -> Select[Tuple[_TModel_0, _TModel_1, _TModel_2, _TScalar_3]]:
     ...
 
@@ -416,7 +389,6 @@ def select(  # type: ignore
     entity_1: Type[_TModel_1],
     entity_2: Type[_TModel_2],
     entity_3: Type[_TModel_3],
-    **kw: Any,
 ) -> Select[Tuple[_TModel_0, _TModel_1, _TModel_2, _TModel_3]]:
     ...
 
@@ -424,10 +396,10 @@ def select(  # type: ignore
 # Generated overloads end
 
 
-def select(*entities: Any, **kw: Any) -> Union[Select, SelectOfScalar]:  # type: ignore
+def select(*entities: Any) -> Union[Select, SelectOfScalar]:  # type: ignore
     if len(entities) == 1:
-        return SelectOfScalar._create(*entities, **kw)  # type: ignore
-    return Select._create(*entities, **kw)  # type: ignore
+        return SelectOfScalar(*entities)  # type: ignore
+    return Select(*entities)  # type: ignore
 
 
 # TODO: add several @overload from Python types to SQLAlchemy equivalents