Post black reformatting

Applied on top of a pure run of black -l 79 in
I7eda77fed3d8e73df84b3651fd6cfcfe858d4dc9,  this set of changes
resolves all remaining flake8 conditions for those codes
we have enabled in setup.cfg.

Included are resolutions for all remaining flake8 issues
including shadowed builtins, long lines, import order, unused
imports, duplicate imports, and docstring issues.

Change-Id: I4f72d3ba1380dd601610ff80b8fb06a2aff8b0fe

3 files changed, 35 insertions, 32 deletions

diff --git a/examples/inheritance/concrete.py b/examples/inheritance/concrete.py
index 2245aa4e0..4eb89984a 100644
--- a/examples/inheritance/concrete.py
+++ b/examples/inheritance/concrete.py
@@ -1,17 +1,17 @@
 """Concrete-table (table-per-class) inheritance example."""
 
-from sqlalchemy import (
-    Column,
-    Integer,
-    String,
-    ForeignKey,
-    create_engine,
-    inspect,
-    or_,
-)
-from sqlalchemy.orm import relationship, Session, with_polymorphic
-from sqlalchemy.ext.declarative import declarative_base
+from sqlalchemy import Column
+from sqlalchemy import create_engine
+from sqlalchemy import ForeignKey
+from sqlalchemy import inspect
+from sqlalchemy import Integer
+from sqlalchemy import or_
+from sqlalchemy import String
 from sqlalchemy.ext.declarative import ConcreteBase
+from sqlalchemy.ext.declarative import declarative_base
+from sqlalchemy.orm import relationship
+from sqlalchemy.orm import Session
+from sqlalchemy.orm import with_polymorphic
 
 
 Base = declarative_base()
diff --git a/examples/inheritance/joined.py b/examples/inheritance/joined.py
index a3a61d763..74a6e3649 100644
--- a/examples/inheritance/joined.py
+++ b/examples/inheritance/joined.py
@@ -1,16 +1,17 @@
 """Joined-table (table-per-subclass) inheritance example."""
 
-from sqlalchemy import (
-    Column,
-    Integer,
-    String,
-    ForeignKey,
-    create_engine,
-    inspect,
-    or_,
-)
-from sqlalchemy.orm import relationship, Session, with_polymorphic
+from sqlalchemy import Column
+from sqlalchemy import create_engine
+from sqlalchemy import ForeignKey
+from sqlalchemy import inspect
+from sqlalchemy import Integer
+from sqlalchemy import or_
+from sqlalchemy import String
 from sqlalchemy.ext.declarative import declarative_base
+from sqlalchemy.orm import relationship
+from sqlalchemy.orm import Session
+from sqlalchemy.orm import with_polymorphic
+
 
 Base = declarative_base()
 
diff --git a/examples/inheritance/single.py b/examples/inheritance/single.py
index 46d690c94..0d5871cb1 100644
--- a/examples/inheritance/single.py
+++ b/examples/inheritance/single.py
@@ -1,16 +1,18 @@
 """Single-table (table-per-hierarchy) inheritance example."""
 
-from sqlalchemy import (
-    Column,
-    Integer,
-    String,
-    ForeignKey,
-    create_engine,
-    inspect,
-    or_,
-)
-from sqlalchemy.orm import relationship, Session, with_polymorphic
-from sqlalchemy.ext.declarative import declarative_base, declared_attr
+from sqlalchemy import Column
+from sqlalchemy import create_engine
+from sqlalchemy import ForeignKey
+from sqlalchemy import inspect
+from sqlalchemy import Integer
+from sqlalchemy import or_
+from sqlalchemy import String
+from sqlalchemy.ext.declarative import declarative_base
+from sqlalchemy.ext.declarative import declared_attr
+from sqlalchemy.orm import relationship
+from sqlalchemy.orm import Session
+from sqlalchemy.orm import with_polymorphic
+
 
 Base = declarative_base()