Support python3.6

Corrects some warnings and adds tox config.  Adds DeprecationWarning
to the error category.   Large sweep for string literals w/ backslashes
as this is common in docstrings

Co-authored-by: Andrii Soldatenko
Fixes: #3886
Change-Id: Ia7c838dfbbe70b262622ed0803d581edc736e085
Pull-request: https://github.com/zzzeek/sqlalchemy/pull/337

1 files changed, 7 insertions, 7 deletions

diff --git a/lib/sqlalchemy/orm/strategy_options.py b/lib/sqlalchemy/orm/strategy_options.py
index 2f98dc72a..bae2b73e2 100644
--- a/lib/sqlalchemy/orm/strategy_options.py
+++ b/lib/sqlalchemy/orm/strategy_options.py
@@ -552,7 +552,7 @@ See :func:`.orm.%(name)s` for usage examples.
 
 @loader_option()
 def contains_eager(loadopt, attr, alias=None):
-    """Indicate that the given attribute should be eagerly loaded from
+    r"""Indicate that the given attribute should be eagerly loaded from
     columns stated manually in the query.
 
     This function is part of the :class:`.Load` interface and supports
@@ -561,8 +561,8 @@ def contains_eager(loadopt, attr, alias=None):
     The option is used in conjunction with an explicit join that loads
     the desired rows, i.e.::
 
-        sess.query(Order).\\
-                join(Order.user).\\
+        sess.query(Order).\
+                join(Order.user).\
                 options(contains_eager(Order.user))
 
     The above query would join from the ``Order`` entity to its related
@@ -575,8 +575,8 @@ def contains_eager(loadopt, attr, alias=None):
     the eagerly-loaded rows are to come from an aliased table::
 
         user_alias = aliased(User)
-        sess.query(Order).\\
-                join((user_alias, Order.user)).\\
+        sess.query(Order).\
+                join((user_alias, Order.user)).\
                 options(contains_eager(Order.user, alias=user_alias))
 
     .. seealso::
@@ -953,7 +953,7 @@ def defaultload(*keys):
 
 @loader_option()
 def defer(loadopt, key):
-    """Indicate that the given column-oriented attribute should be deferred, e.g.
+    r"""Indicate that the given column-oriented attribute should be deferred, e.g.
     not loaded until accessed.
 
     This function is part of the :class:`.Load` interface and supports
@@ -1017,7 +1017,7 @@ def defer(key, *addl_attrs):
 
 @loader_option()
 def undefer(loadopt, key):
-    """Indicate that the given column-oriented attribute should be undeferred,
+    r"""Indicate that the given column-oriented attribute should be undeferred,
     e.g. specified within the SELECT statement of the entity as a whole.
 
     The column being undeferred is typically set up on the mapping as a