diff --git a/grumpy-tools-src/grumpy_tools/benchcmp.py b/grumpy-tools-src/grumpy_tools/benchcmp.py
index be4dafc2..eced9512 100755
--- a/grumpy-tools-src/grumpy_tools/benchcmp.py
+++ b/grumpy-tools-src/grumpy_tools/benchcmp.py
@@ -16,10 +16,16 @@
 
 """Runs two benchmark programs and compares their results."""
 
+from __future__ import print_function
+
 import argparse
 import subprocess
 import sys
 
+try:
+  xrange          # Python 2
+except NameError:
+  xrange = range  # Python 3
 
 parser = argparse.ArgumentParser()
 parser.add_argument('prog1')
@@ -37,7 +43,7 @@ def main(args):
     _MergeResults(results2, _RunBenchmark(args.prog2), benchmarks)
   _MergeResults(results2, _RunBenchmark(args.prog2), benchmarks)
   for b in sorted(benchmarks):
-    print b, '{:+.1%}'.format(results2[b] / results1[b] - 1)
+    print(b, '{:+.1%}'.format(results2[b] / results1[b] - 1))
 
 
 def _MergeResults(merged, results, benchmarks):
@@ -65,10 +71,10 @@ def _RunBenchmark(prog):
     line = line.strip()
     if not line:
       continue
-    parts = line.split()
-    if len(parts) != 3:
+    try:
+      name, status, result = line.split()
+    except ValueError:
       _Die('invalid benchmark output: {}', line)
-    name, status, result = parts
     if status != 'PASSED':
       _Die('benchmark failed: {}', line)
     try:
@@ -82,7 +88,7 @@ def _RunBenchmark(prog):
 def _Die(msg, *args):
   if args:
     msg = msg.format(*args)
-  print >> sys.stderr, msg
+  print(msg, file=sys.stderr)
   sys.exit(1)
 
 
diff --git a/grumpy-tools-src/grumpy_tools/compiler/imputil.py b/grumpy-tools-src/grumpy_tools/compiler/imputil.py
index b7a9fb89..cebb5298 100644
--- a/grumpy-tools-src/grumpy_tools/compiler/imputil.py
+++ b/grumpy-tools-src/grumpy_tools/compiler/imputil.py
@@ -30,6 +30,11 @@
 from grumpy_tools.vendor.pythonparser import algorithm
 from grumpy_tools.vendor.pythonparser import ast
 
+try:
+  xrange          # Python 2
+except NameError:
+  xrange = range  # Python 3
+
 
 _NATIVE_MODULE_PREFIX = '__go__/'
 
diff --git a/grumpy-tools-src/grumpy_tools/coverparse.py b/grumpy-tools-src/grumpy_tools/coverparse.py
index d8b72aba..a63e6fce 100755
--- a/grumpy-tools-src/grumpy_tools/coverparse.py
+++ b/grumpy-tools-src/grumpy_tools/coverparse.py
@@ -16,10 +16,16 @@
 
 """Parse a Go coverage file and prints a message for lines missing coverage."""
 
+from __future__ import print_function
+
 import collections
 import re
 import sys
 
+try:
+  xrange          # Python 2
+except NameError:
+  xrange = range  # Python 3
 
 cover_re = re.compile(r'([^:]+):(\d+)\.\d+,(\d+).\d+ \d+ (\d+)$')
 
@@ -44,7 +50,7 @@ def main():
     uncovered = _ParseCover(f)
   for filename in sorted(uncovered.keys()):
     for lineno in sorted(uncovered[filename]):
-      print '{}:{}'.format(filename, lineno)
+      print('{}:{}'.format(filename, lineno))
 
 
 if __name__ == '__main__':
diff --git a/grumpy-tools-src/grumpy_tools/diffrange.py b/grumpy-tools-src/grumpy_tools/diffrange.py
index ea60fb0f..c56f4291 100755
--- a/grumpy-tools-src/grumpy_tools/diffrange.py
+++ b/grumpy-tools-src/grumpy_tools/diffrange.py
@@ -16,6 +16,8 @@
 
 """Convert a unified diff into a list of modified files and line numbers."""
 
+from __future__ import print_function
+
 import sys
 
 
@@ -76,7 +78,7 @@ def main():
     if line.startswith('+++'):
       filename = line.split()[1]
       for n in _ReadHunks(buf):
-        print '{}:{}'.format(filename, n)
+        print('{}:{}'.format(filename, n))
 
 
 if __name__ == '__main__':
diff --git a/grumpy-tools-src/grumpy_tools/genmake.py b/grumpy-tools-src/grumpy_tools/genmake.py
index c13465a5..774617f6 100755
--- a/grumpy-tools-src/grumpy_tools/genmake.py
+++ b/grumpy-tools-src/grumpy_tools/genmake.py
@@ -16,6 +16,8 @@
 
 """Generate a Makefile for Python targets in a GOPATH directory."""
 
+from __future__ import print_function
+
 import argparse
 import os
 import subprocess
@@ -29,12 +31,12 @@
 
 
 def _PrintRule(target, prereqs, rules):
-  print '{}: {}'.format(target, ' '.join(prereqs))
+  print('{}: {}'.format(target, ' '.join(prereqs)))
   if rules:
-    print '\t@mkdir -p $(@D)'
+    print('\t@mkdir -p $(@D)')
     for rule in rules:
-      print '\t@{}'.format(rule)
-  print
+      print('\t@{}'.format(rule))
+  print()
 
 
 def main(args):
@@ -42,16 +44,16 @@ def main(args):
     proc = subprocess.Popen('go env GOOS GOARCH', shell=True,
                             stdout=subprocess.PIPE)
   except OSError as e:
-    print >> sys.stderr, str(e)
+    print(str(e), file=sys.stderr)
     return 1
   out, _ = proc.communicate()
   if proc.returncode:
-    print >> sys.stderr, 'go exited with status: {}'.format(proc.returncode)
+    print('go exited with status: {}'.format(proc.returncode), file=sys.stderr)
     return 1
   goos, goarch = out.split()
 
   if args.all_target:
-    print '{}:\n'.format(args.all_target)
+    print('{}:\n'.format(args.all_target))
 
   gopath = os.path.normpath(args.dir)
   pkg_dir = os.path.join(gopath, 'pkg', '{}_{}'.format(goos, goarch))
@@ -80,7 +82,7 @@ def main(args):
       _PrintRule(ar_name, [go_file], [recipe.format(go_package, pkg_dir)])
       if args.all_target:
         _PrintRule(args.all_target, [ar_name], [])
-      print '-include {}\n'.format(dep_file)
+      print('-include {}\n'.format(dep_file))
 
 
 if __name__ == '__main__':
diff --git a/grumpy-tools-src/grumpy_tools/pydeps.py b/grumpy-tools-src/grumpy_tools/pydeps.py
index 5bd6f56c..a26d9de4 100755
--- a/grumpy-tools-src/grumpy_tools/pydeps.py
+++ b/grumpy-tools-src/grumpy_tools/pydeps.py
@@ -23,6 +23,11 @@
 from .compiler import imputil
 from .compiler import util
 
+try:
+  xrange          # Python 2
+except NameError:
+  xrange = range  # Python 3
+
 
 def main(script=None, modname=None, package_dir='', with_imports=False):
   gopath = os.environ['GOPATH']
diff --git a/grumpy-tools-src/grumpy_tools/vendor/pythonparser/lexer.py b/grumpy-tools-src/grumpy_tools/vendor/pythonparser/lexer.py
index 13c28155..d578b885 100644
--- a/grumpy-tools-src/grumpy_tools/vendor/pythonparser/lexer.py
+++ b/grumpy-tools-src/grumpy_tools/vendor/pythonparser/lexer.py
@@ -11,6 +11,7 @@
 if sys.version_info[0] == 3:
     unichr = chr
     byte = lambda x: bytes([x])
+    long = int
 else:
     byte = chr
 
diff --git a/grumpy-tools-src/tests/havingmainpkg/__main__.py b/grumpy-tools-src/tests/havingmainpkg/__main__.py
index 5e396af8..fae4cabc 100644
--- a/grumpy-tools-src/tests/havingmainpkg/__main__.py
+++ b/grumpy-tools-src/tests/havingmainpkg/__main__.py
@@ -1,13 +1,14 @@
-import sys
+from __future__ import print_function
+
 
 def main():
-    print '__name__ is', __name__
-    print '__package__ is', __package__
+    print('__name__ is', __name__)
+    print('__package__ is', __package__)
     from . import SPAM
     print(SPAM)
 
 
 if __name__ == '__main__':
-    print '__name__ IS __main__'
-    print '__package__ is', __package__
+    print('__name__ IS __main__')
+    print('__package__ is', __package__)
     main()
diff --git a/grumpy-tools-src/tests/import_havingpkgmain.py b/grumpy-tools-src/tests/import_havingpkgmain.py
index 8348d4fa..c0dcfbb9 100644
--- a/grumpy-tools-src/tests/import_havingpkgmain.py
+++ b/grumpy-tools-src/tests/import_havingpkgmain.py
@@ -1,6 +1,8 @@
-print 'STARTING'
+from __future__ import print_function
+
+print('STARTING')
 from havingmainpkg.__main__ import main
-print 'IMPORTED'
+print('IMPORTED')
 
 main()
-print 'CALLED main()'
+print('CALLED main()')