cause a subsequent call to the :meth:`.Query.with_parent` method to
fail. fixes #3606
- add mark-as-fail test for #3607

(cherry picked from commit 6b87e0b301f123359f8a32114a3e888d6dd05bfc)

to the :class:`.mutable.MutableDict` class.
fixes #3605

back_populates while still maintaining great familiarity
w/ backref so as not to confuse people.  fixes #3390

are now exercised within the normal unit test suite in both Python
2 and Python 3.
- remove the old testdocs.py runner and replace with test/base/test_tutorials.py
- use pytest's unicode fixer so that we can test for unicode strings
in both py2k/3k
- use py3k format overall for prints, exceptions
- add other fixers to guarantee deterministic results
- add skips and ellipses to outputs that aren't worth matching

Includes removal of adapt_like_to_iterable() as well
as _set_iterable(), uses __slots__ for collectionadapter,
does much less duck typing of collections.

the :class:`.Select` construct would have its ``._raw_columns``
collection mutated in-place when compiling the :class:`.Insert`
construct, when the target :class:`.Table` has Python-side defaults.
The :class:`.Select` construct would compile standalone with the
erroneous column present subsequent to compilation of the
:class:`.Insert`, and the the :class:`.Insert` statement itself would
fail on a second compile attempt due to duplicate bound parameters.
fixes #3603