fixed code and test for Python3

dataset/freeze/format/fcsv.py

@@ -1,13 +1,15 @@
 import csv
 from datetime import datetime
 
+from six import PY3
+
 from dataset.freeze.format.common import Serializer
 
 
 def value_to_str(value):
     if isinstance(value, datetime):
         return value.isoformat()
-    if hasattr(value, 'encode'):
+    if not PY3 and hasattr(value, 'encode'):
         return value.encode('utf-8')
     if value is None:
         return ''

setup.py

@@ -33,7 +33,8 @@ setup(
         'sqlalchemy >= 0.9.1',
         'alembic >= 0.6.2',
         'python-slugify >= 0.0.6',
-        "PyYAML >= 3.10"
+        "PyYAML >= 3.10",
+        "six >= 1.7.3"
     ] + py26_dependency,
     tests_require=[],
     test_suite='test',

test/test_freeze.py

@@ -1,5 +1,8 @@
 # -*- encoding: utf-8 -*-
 import unittest
+
+from six import PY3
+
 from dataset.freeze.format.fcsv import value_to_str
 
 from .sample_data import TEST_DATA
@@ -11,7 +14,10 @@ class FreezeTestCase(unittest.TestCase):
         assert '2011-01-01T00:00:00' == value_to_str(TEST_DATA[0]['date'])
 
     def test_value_to_str2(self):
-        assert 'hóla' == value_to_str(u'\u0068\u00f3\u006c\u0061')
+        if PY3:
+            assert 'hóla' == value_to_str('\u0068\u00f3\u006c\u0061')
+        else:
+            assert 'hóla' == value_to_str(u'\u0068\u00f3\u006c\u0061')
 
     def test_value_to_str3(self):
         assert '' == value_to_str(None)