This is a very useful assertion which prevents unused variables
from being set up allows code to be more readable and sometimes
even more efficient.  test suites seem to be where the most
problems are and there do not seem to be documentation examples
that are using this, or at least the linter is not taking effect
within rst blocks.

Change-Id: I2b3341d8dd14da34879d8425838e66a4b9f8e27d

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

This is a straight reformat run using black as is, with no edits
applied at all.

The black run will format code consistently, however in
some cases that are prevalent in SQLAlchemy code it produces
too-long lines.   The too-long lines will be resolved in the
following commit that will resolve all remaining flake8 issues
including shadowed builtins, long lines, import order, unused
imports, duplicate imports, and docstring issues.

Change-Id: I7eda77fed3d8e73df84b3651fd6cfcfe858d4dc9

Fixes to the test suite, a few errant imports, and setup.py:

- mysql and postgresql have unused 'json' imports; remove
- postgresql is exporting the 'json' symbol, remove
- make sure setup.py can find __version__ using " or '
- retry logic in provision create database for postgresql fixed
- refactor test_magazine to use cls.tables rather than globals
- remove unused class in test_scoping
- add a comment to test_deprecations that this test suite itself
  is deprecated
- don't use mapper() and orm_mapper() in test_unitofwork, just
  use mapper()
- remove dupe test_scalar_set_None test in test_attributes
- Python 2.7 and above includes unittest.SkipTest, remove pre-2.7
  fallback
- use imported SkipTest in profiling
- declarative test_reflection tests with "reflectable_autoincrement"
  already don't run on oracle or firebird; remove conditional logic
  for these, which also removes an "id" symbol
- clean up test in test_functions, remove print statement
- remove dupe test_literal_processor_coercion_native_int_out_of_range
  in test/sql/test_types.py
- fix psycopg2_hstore ref

Change-Id: I7b3444f8546aac82be81cd1e7b6d8b2ad6834fe6

Removed a very old keyword argument from :class:`.scoped_session`
called ``scope``.  This keyword was never documented and was an
early attempt at allowing for variable scopes.

Change-Id: I9a26498a1a66d1eafb0723e98b527688a60f9d9b
Fixes: #3796

tested using pycodestyle version 2.2.0

Fixes: #3885
Change-Id: I5df43adc3aefe318f9eeab72a078247a548ec566
Pull-request: https://github.com/zzzeek/sqlalchemy/pull/343

become an externally usable package but still remains within the main sqlalchemy parent package.
in this system, we use kind of an ugly hack to get the noseplugin imported outside of the
"sqlalchemy" package, while still making it available within sqlalchemy for usage by
third party libraries.

- remove extra _load_fixtures() method.   using the classbound version as the fixtures
seem to have everything classlevel at the moment (wondering if we want to change that
for non-classlevel setup/teardown)

- move testing.TestBase to test.lib.fixtures
- massive search and replace

access to the cls/self.tables/classes registries
- express orm/_base.py ORMTest in terms of engine/_base.py TablesTest,
factor out common steps into TablesTest, remove AltEngineTest as a
separate class.   will further consolidate these base classes