1 files changed, 16 insertions, 9 deletions
diff --git a/lib/sqlalchemy/orm/exc.py b/lib/sqlalchemy/orm/exc.py
index eb4baa08d..f0aa02e99 100644
--- a/lib/sqlalchemy/orm/exc.py
+++ b/lib/sqlalchemy/orm/exc.py
@@ -38,6 +38,7 @@ class StaleDataError(sa_exc.SQLAlchemyError):
 
     """
 
+
 ConcurrentModificationError = StaleDataError
 
 
@@ -72,16 +73,19 @@ class UnmappedInstanceError(UnmappedError):
             try:
                 base.class_mapper(type(obj))
                 name = _safe_cls_name(type(obj))
-                msg = ("Class %r is mapped, but this instance lacks "
-                       "instrumentation.  This occurs when the instance "
-                       "is created before sqlalchemy.orm.mapper(%s) "
-                       "was called." % (name, name))
+                msg = (
+                    "Class %r is mapped, but this instance lacks "
+                    "instrumentation.  This occurs when the instance "
+                    "is created before sqlalchemy.orm.mapper(%s) "
+                    "was called." % (name, name)
+                )
             except UnmappedClassError:
                 msg = _default_unmapped(type(obj))
                 if isinstance(obj, type):
                     msg += (
-                        '; was a class (%s) supplied where an instance was '
-                        'required?' % _safe_cls_name(obj))
+                        "; was a class (%s) supplied where an instance was "
+                        "required?" % _safe_cls_name(obj)
+                    )
         UnmappedError.__init__(self, msg)
 
     def __reduce__(self):
@@ -119,11 +123,14 @@ class ObjectDeletedError(sa_exc.InvalidRequestError):
     object.
 
     """
+
     @util.dependencies("sqlalchemy.orm.base")
     def __init__(self, base, state, msg=None):
         if not msg:
-            msg = "Instance '%s' has been deleted, or its "\
+            msg = (
+                "Instance '%s' has been deleted, or its "
                 "row is otherwise not present." % base.state_str(state)
+            )
 
         sa_exc.InvalidRequestError.__init__(self, msg)
 
@@ -145,9 +152,9 @@ class MultipleResultsFound(sa_exc.InvalidRequestError):
 
 def _safe_cls_name(cls):
     try:
-        cls_name = '.'.join((cls.__module__, cls.__name__))
+        cls_name = ".".join((cls.__module__, cls.__name__))
     except AttributeError:
-        cls_name = getattr(cls, '__name__', None)
+        cls_name = getattr(cls, "__name__", None)
         if cls_name is None:
             cls_name = repr(cls)
     return cls_name