No need for binary type

transaction/_compat.py

@@ -9,14 +9,12 @@ if PY3: # pragma: no cover
     integer_types = int,
     class_types = type,
     text_type = str
-    binary_type = bytes
     long = int
 else:
     string_types = basestring,
     integer_types = (int, long)
     class_types = (type, types.ClassType)
     text_type = unicode
-    binary_type = str
     long = long
 
 def bytes_(s, encoding='latin-1', errors='strict'): #pragma NO COVER

transaction/_transaction.py

@@ -23,7 +23,6 @@ from zope.interface import implementer
 from transaction.weakset import WeakSet
 from transaction.interfaces import TransactionFailedError
 from transaction import interfaces
-from transaction._compat import binary_type
 from transaction._compat import reraise
 from transaction._compat import get_thread_ident
 from transaction._compat import native_
@@ -760,7 +759,7 @@ def text_or_warn(s):
         return s
 
     warnings.warn("Expected text", DeprecationWarning, stacklevel=3)
-    if isinstance(s, binary_type):
+    if isinstance(s, bytes):
         return s.decode('utf-8', 'replace')
     else:
         return text_type(s)