diff --git a/.travis.yml b/.travis.yml
index 6c84fed..84f25ff 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,7 +2,7 @@ language: python
 python:
   - "2.6"
   - "2.7"
-  #- "3.3"
+  - "3.3"
 # command to install dependencies
 install: "pip install -r requirements.txt --use-mirrors"
 # command to run tests
diff --git a/lesscpy/lessc/color.py b/lesscpy/lessc/color.py
index f10683e..c0da7fa 100644
--- a/lesscpy/lessc/color.py
+++ b/lesscpy/lessc/color.py
@@ -62,7 +62,7 @@ class Color():
             return self.rgba(*args)
         elif len(args) == 3:
             try:
-                return self._rgbatohex(map(int, args))
+                return self._rgbatohex(list(map(int, args)))
             except ValueError:
                 if all((a for a in args
                         if a[-1] == '%'
@@ -80,7 +80,7 @@ class Color():
         """
         if len(args) == 4:
             try:
-                return self._rgbatohex(map(int, args))
+                return self._rgbatohex(list(map(int, args)))
             except ValueError:
                 if all((a for a in args
                         if a[-1] == '%'
diff --git a/lesscpy/lessc/lexer.py b/lesscpy/lessc/lexer.py
index 662f776..e03d86a 100644
--- a/lesscpy/lessc/lexer.py
+++ b/lesscpy/lessc/lexer.py
@@ -84,7 +84,7 @@ class LessLexer:
     def __init__(self):
         self.build(reflags=re.UNICODE | re.IGNORECASE)
         self.last = None
-        self.next = None
+        self.next_ = None
         self.pretok = True
 
     def t_css_filter(self, t):
@@ -256,9 +256,9 @@ class LessLexer:
             2.  Strips out whitespace from nonsignificant locations
                 to ease parsing.
         """
-        if self.next:
-            t = self.next
-            self.next = None
+        if self.next_:
+            t = self.next_
+            self.next_ = None
             return t
         while True:
             t = self.lexer.token()
@@ -270,7 +270,7 @@ class LessLexer:
                 continue
             self.pretok = False
             if t.type == '}' and self.last and self.last.type not in '{;}':
-                self.next = t
+                self.next_ = t
                 tok = lex.LexToken()
                 tok.type = ';'
                 tok.value = ';'
diff --git a/lesscpy/lessc/parser.py b/lesscpy/lessc/parser.py
index a744679..d45c15f 100644
--- a/lesscpy/lessc/parser.py
+++ b/lesscpy/lessc/parser.py
@@ -1,4 +1,3 @@
-from __future__ import print_function
 # -*- coding: utf8 -*-
 """
 .. module:: lesscpy.lessc.parser
@@ -12,9 +11,13 @@ from __future__ import print_function
     See LICENSE for details.
 .. moduleauthor:: Johann T. Mariusson <jtm@robot.is>
 """
+
+from __future__ import print_function
+
 import os
 import sys
 import ply.yacc
+
 from . import lexer
 from . import utility
 from .scope import Scope
diff --git a/lesscpy/lessc/utility.py b/lesscpy/lessc/utility.py
index b74cb7f..33977a4 100644
--- a/lesscpy/lessc/utility.py
+++ b/lesscpy/lessc/utility.py
@@ -7,6 +7,9 @@
     See LICENSE for details.
 .. moduleauthor:: Johann T. Mariusson <jtm@robot.is>
 """
+
+from __future__ import print_function
+
 import collections
 import re
 
diff --git a/lesscpy/plib/mixin.py b/lesscpy/plib/mixin.py
index aec9d73..75ead7e 100644
--- a/lesscpy/plib/mixin.py
+++ b/lesscpy/plib/mixin.py
@@ -56,7 +56,7 @@ class Mixin(Node):
         raises:
             SyntaxError
         """
-        arguments = zip(args, [' '] * len(args)) if args and args[0] else None
+        arguments = list(zip(args, [' '] * len(args))) if args and args[0] else None
         zl = itertools.zip_longest if sys.version_info[
             0] == 3 else itertools.izip_longest
         if self.args:
diff --git a/lesscpy/scripts/compiler.py b/lesscpy/scripts/compiler.py
index d3db996..f6b92c7 100644
--- a/lesscpy/scripts/compiler.py
+++ b/lesscpy/scripts/compiler.py
@@ -1,4 +1,3 @@
-from __future__ import print_function
 # -*- coding: utf8 -*-
 """
 .. module:: lesscpy.scripts.compiler
@@ -10,11 +9,15 @@ from __future__ import print_function
     See LICENSE for details
 .. moduleauthor:: Johann T. Mariusson <jtm@robot.is>
 """
+
+from __future__ import print_function
+
 import os
 import sys
 import glob
 import copy
 import argparse
+
 sys.path.append(os.path.abspath(os.path.dirname(__file__)))
 from lesscpy.lessc import parser
 from lesscpy.lessc import lexer
diff --git a/tox.ini b/tox.ini
index 1d001e0..e1744d8 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-envlist = py26,py27,pep8
+envlist = py26,py27,py33,pep8
 
 [testenv]
 deps = -r{toxinidir}/requirements.txt