Merge "Enable F821"

2 files changed, 9 insertions, 2 deletions

diff --git a/lib/sqlalchemy/util/__init__.py b/lib/sqlalchemy/util/__init__.py
index c1790439c..a19636f62 100644
--- a/lib/sqlalchemy/util/__init__.py
+++ b/lib/sqlalchemy/util/__init__.py
@@ -80,6 +80,7 @@ from .compat import StringIO  # noqa
 from .compat import text_type  # noqa
 from .compat import threading  # noqa
 from .compat import timezone  # noqa
+from .compat import TYPE_CHECKING  # noqa
 from .compat import u  # noqa
 from .compat import ue  # noqa
 from .compat import unquote  # noqa
diff --git a/lib/sqlalchemy/util/compat.py b/lib/sqlalchemy/util/compat.py
index 82bf68d2c..2cb5db5d4 100644
--- a/lib/sqlalchemy/util/compat.py
+++ b/lib/sqlalchemy/util/compat.py
@@ -158,6 +158,8 @@ if py3k:
     def ue(s):
         return s
 
+    from typing import TYPE_CHECKING
+
     # Unused. Kept for backwards compatibility.
     callable = callable  # noqa
 else:
@@ -244,8 +246,10 @@ else:
     def safe_bytestring(text):
         # py2k only
         if not isinstance(text, string_types):
-            return unicode(text).encode("ascii", errors="backslashreplace")
-        elif isinstance(text, unicode):
+            return unicode(text).encode(  # noqa: F821
+                "ascii", errors="backslashreplace"
+            )
+        elif isinstance(text, unicode):  # noqa: F821
             return text.encode("ascii", errors="backslashreplace")
         else:
             return text
@@ -259,6 +263,8 @@ else:
         "    raise tp, value, tb\n"
     )
 
+    TYPE_CHECKING = False
+
 
 if py35:
     from inspect import formatannotation