diff --git a/PRESUBMIT.py b/PRESUBMIT.py
index 1c246c1226..856478a808 100644
--- a/PRESUBMIT.py
+++ b/PRESUBMIT.py
@@ -27,8 +27,6 @@ SERVICE_ACCOUNT_SUFFIX = [
         'skia-buildbots.google.com', 'skia-swarming-bots', 'skia-public',
         'skia-corp.google.com', 'chops-service-accounts']]
 
-USE_PYTHON3 = True
-
 
 def _CheckChangeHasEol(input_api, output_api, source_file_filter=None):
   """Checks that files end with at least one \n (LF)."""
diff --git a/infra/bots/infra_tests.py b/infra/bots/infra_tests.py
index 7d162cb9eb..0e226b546c 100755
--- a/infra/bots/infra_tests.py
+++ b/infra/bots/infra_tests.py
@@ -21,7 +21,7 @@ SKIA_DIR = os.path.abspath(os.path.join(INFRA_BOTS_DIR, os.pardir, os.pardir))
 
 def test(cmd, cwd):
   try:
-    subprocess.check_output(cmd, cwd=cwd, stderr=subprocess.STDOUT, encoding='utf-8')
+    subprocess.check_output(cmd, cwd=cwd, stderr=subprocess.STDOUT)
   except subprocess.CalledProcessError as e:
     return e.output
 
diff --git a/tools/rewrite_includes.py b/tools/rewrite_includes.py
index 980c2ef81d..df4474aa1f 100755
--- a/tools/rewrite_includes.py
+++ b/tools/rewrite_includes.py
@@ -8,9 +8,10 @@
 
 import argparse
 import os
+import six
 import sys
 
-from io import StringIO
+from six import StringIO
 
 
 parser = argparse.ArgumentParser()