diff --git a/quixote/config.py b/quixote/config.py
index 75b6acb..bd1a4fb 100644
--- a/quixote/config.py
+++ b/quixote/config.py
@@ -164,7 +164,7 @@ class Config:
         config_vars = {}
         try:
             execfile(filename, config_vars)
-        except IOError, exc:
+        except IOError as exc:
             if exc.filename is None:    # arg! execfile() loses filename
                 exc.filename = filename
             raise exc
diff --git a/quixote/http_response.py b/quixote/http_response.py
index b4fb835..843fbe5 100644
--- a/quixote/http_response.py
+++ b/quixote/http_response.py
@@ -538,7 +538,7 @@ class HTTPResponse:
             output.write(s.encode('utf-8'))
 
         for name, value in self.generate_headers():
-            s = "%s: %s\r\n" % (name, value))
+            s = "%s: %s\r\n" % (name, value)
             output.write(s.encode('utf-8'))
         output.write(b"\r\n")
         if flush_output:
diff --git a/quixote/ptl/test/utest_ptl.py b/quixote/ptl/test/utest_ptl.py
index d9a8258..ecc50fd 100755
--- a/quixote/ptl/test/utest_ptl.py
+++ b/quixote/ptl/test/utest_ptl.py
@@ -1,7 +1,7 @@
 #!/usr/bin/env python
 from sancho.utest import UTest
 from quixote.ptl.ptl_compile import compile_template
-from StringIO import StringIO
+from io import StringIO
 from quixote.html import TemplateIO, htmltext
 
 def run_ptl(*source):
@@ -45,12 +45,12 @@ class Test (UTest):
         try:
             run_ptl('def f [] (a):\n    a')
             assert 0
-        except SyntaxError, e:
+        except SyntaxError as e:
             assert e.lineno == 1
         try:
             run_ptl('def f [HTML] (a):\n    a')
             assert 0
-        except SyntaxError, e:
+        except SyntaxError as e:
             assert e.lineno == 1
 
 if __name__ == "__main__":
diff --git a/setup.py b/setup.py
index c82fa26..081833a 100644
--- a/setup.py
+++ b/setup.py
@@ -1,14 +1,17 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #try:
 #    from setuptools import setup
 #except ImportError:
-#    print '(WARNING: importing distutils, not setuptools!)'
+#    print('(WARNING: importing distutils, not setuptools!)')
 #    from distutils.core import setup
 
 # Setup script for Quixote
 
 import sys
-import os
+
+if sys.version_info < (3,4,0):
+    raise SystemExit("You need python 3.4.0 or later to run this script")
+
 from distutils import core
 from distutils.extension import Extension
 from quixote.ptl.qx_distutils import qx_build_py