diff --git a/src/allmydata/test/_win_subprocess.py b/src/allmydata/test/_win_subprocess.py
index 2c2cb60b4..bf9767e73 100644
--- a/src/allmydata/test/_win_subprocess.py
+++ b/src/allmydata/test/_win_subprocess.py
@@ -7,6 +7,9 @@ from future.utils import PY3
 if PY3:
     raise RuntimeError("Just use subprocess.Popen")
 
+# This is necessary to pacify flake8 on Python 3, while we're still supporting
+# Python 2.
+from past.builtins import unicode
 
 # -*- coding: utf-8 -*-
 
diff --git a/src/allmydata/test/web/test_grid.py b/src/allmydata/test/web/test_grid.py
index ef2718df4..edcf32268 100644
--- a/src/allmydata/test/web/test_grid.py
+++ b/src/allmydata/test/web/test_grid.py
@@ -660,7 +660,6 @@ class Grid(GridTestMixin, WebErrorMixin, ShouldFailMixin, testutil.ReallyEqualMi
                          if line]
             except ValueError:
                 print("response is:", res)
-                print("undecodeable line was '%s'" % line)
                 raise
             self.failUnlessReallyEqual(len(units), 5+1)
             # should be parent-first
diff --git a/src/allmydata/uri.py b/src/allmydata/uri.py
index 70742b7b2..5641771d3 100644
--- a/src/allmydata/uri.py
+++ b/src/allmydata/uri.py
@@ -16,7 +16,7 @@ if PY2:
     # Don't import bytes or str, to prevent future's newbytes leaking and
     # breaking code that only expects normal bytes.
     from future.builtins import filter, map, zip, ascii, chr, hex, input, next, oct, open, pow, round, super, dict, list, object, range, max, min  # noqa: F401
-    str = unicode
+    from past.builtins import unicode as str
 
 from past.builtins import unicode, long
 
diff --git a/src/allmydata/windows/registry.py b/src/allmydata/windows/registry.py
index 2c7f03156..a5426cb75 100644
--- a/src/allmydata/windows/registry.py
+++ b/src/allmydata/windows/registry.py
@@ -32,7 +32,7 @@ def get_registry_setting(key, name, _topkey=None):
             regkey = winreg.OpenKey(topkey, key)
 
             sublen, vallen, timestamp = winreg.QueryInfoKey(regkey)
-            for validx in xrange(vallen):
+            for validx in range(vallen):
                 keyname, value, keytype = winreg.EnumValue(regkey, validx)
                 if keyname == name and keytype == winreg.REG_SZ:
                     return value