diff --git a/pypytools/pypylog/model.py b/pypytools/pypylog/model.py
index 9d97b21..14384b0 100644
--- a/pypytools/pypylog/model.py
+++ b/pypytools/pypylog/model.py
@@ -1,8 +1,12 @@
-import itertools
 from collections import defaultdict
 import attr
 import numpy as np
 
+try:
+    from itertools import izip as zip
+except ImportError: # will be 3.x series
+    pass
+
 @attr.s
 class Event(object):
     tsid = attr.ib() # unique identifier for an event
@@ -46,15 +50,15 @@ def add_event(self, ev):
 
     def print_summary(self):
         fmt = '%-28s %6s %8s'
-        print fmt % ('section', 'n', 'delta')
-        print '-'*44
+        print(fmt % ('section', 'n', 'delta'))
+        print('-'*44)
         for name, events in sorted(self.sections.iteritems()):
             total = 0
             for ev in events:
                 delta = ev.end - ev.start
                 assert delta >= 0
                 total += delta
-            print fmt % (name, len(events), format(delta, '.4f'))
+            print(fmt % (name, len(events), format(delta, '.4f')))
 
 class Series(object):
 
@@ -79,7 +83,7 @@ def __len__(self):
         return len(self.X)
 
     def __iter__(self):
-        for x, y in itertools.izip(self.X, self.Y):
+        for x, y in zip(self.X, self.Y):
             yield x, y
 
     def __getitem__(self, i):
diff --git a/pypytools/pypylog/parse.py b/pypytools/pypylog/parse.py
index c252904..43b3b20 100644
--- a/pypytools/pypylog/parse.py
+++ b/pypytools/pypylog/parse.py
@@ -35,6 +35,11 @@ def parse_file(f):
         #
         if log is None:
             log = model.PyPyLog()
+        try:
+        # Python 2: "basestring" is built-in
+            basestring
+        except NameError:
+            basestring = str
         if isinstance(fname, basestring):
             with open(fname) as f:
                 return parse_file(f)
diff --git a/pypytools/pypylog/testing/test_parse.py b/pypytools/pypylog/testing/test_parse.py
index 20416bc..d071971 100644
--- a/pypytools/pypylog/testing/test_parse.py
+++ b/pypytools/pypylog/testing/test_parse.py
@@ -1,6 +1,13 @@
 import pytest
 import textwrap
-from cStringIO import StringIO
+
+from pypytools.util import PY3
+
+if PY3:
+    from io import StringIO
+else:
+    from cStringIO import StringIO
+
 from pypytools.pypylog import parse
 from pypytools.pypylog import model
 from pypytools.pypylog.model import Event, GcMinor, GcCollectStep
@@ -33,7 +40,11 @@ def test_mismatch(self):
         [456] foo}
         [0ab] bar}
         """
-        pytest.raises(parse.ParseError, "self.parse(log)")
+        with pytest.raises(
+            parse.ParseError,
+            match=r'^End section does not match start: expected bar, got foo$',
+        ):
+            self.parse(log)
 
     def test_nested(self):
         log = self.parse("""
@@ -124,4 +135,5 @@ def test_parse_frequency():
     assert pf('40 KHz') == 40e3
     assert pf('40 MHz') == 40e6
     assert pf('40 GHz') == 40e9
-    pytest.raises(ValueError, "pf('')")
+    with pytest.raises(ValueError, match=r'^$'):
+        pf('')
diff --git a/pypytools/util.py b/pypytools/util.py
index a0cd85b..102452d 100644
--- a/pypytools/util.py
+++ b/pypytools/util.py
@@ -2,6 +2,7 @@
 from sys import version_info
 
 PY3 = version_info.major == 3
+PY3M = version_info.minor
 
 def clonefunc(f):
     """Deep clone the given function to create a new one.
@@ -22,6 +23,11 @@ def clonefunc(f):
             co.co_firstlineno, co.co_lnotab, co.co_freevars, co.co_cellvars]
     if PY3:
         args.insert(1, co.co_kwonlyargcount)
+    if PY3 and PY3M >= 8:
+        args.insert(1, co.co_posonlyargcount)
+    if PY3 and PY3M >= 11:
+        args.insert(12, co.co_qualname)
+        args.insert(15, co.co_exceptiontable)
     co2 = types.CodeType(*args)
     #
     # then, we clone the function itself, using the new co2