diff --git a/questionnaire/qprocessors/timeperiod.py b/questionnaire/qprocessors/timeperiod.py
index ff22316..7698398 100644
--- a/questionnaire/qprocessors/timeperiod.py
+++ b/questionnaire/qprocessors/timeperiod.py
@@ -40,7 +40,7 @@ def question_timeperiod(request, question):
 
 @answer_proc('timeperiod')
 def process_timeperiod(question, answer):
-    if not answer['ANSWER'] or not 'unit in 'answer:
+    if not answer['ANSWER'] or not 'unit' in answer:
         raise AnswerException(_(u"Invalid time period"))
     period = answer['ANSWER'].strip()
     if period:
diff --git a/questionnaire/utils.py b/questionnaire/utils.py
index d058218..3b1bce0 100644
--- a/questionnaire/utils.py
+++ b/questionnaire/utils.py
@@ -1,6 +1,6 @@
 #!/usr/bin/python
 import codecs
-import cStringIO
+from six import StringIO
 import csv
 from six import text_type as unicodestr
 
@@ -71,7 +71,7 @@ class UnicodeWriter:
 
     def __init__(self, f, dialect=csv.excel, encoding="utf-8", **kwds):
         # Redirect output to a queue
-        self.queue = cStringIO.StringIO()
+        self.queue = StringIO()
         self.writer = csv.writer(self.queue, dialect=dialect, **kwds)
         self.stream = f
         self.encoder = codecs.getincrementalencoder(encoding)()
diff --git a/setup.py b/setup.py
index db5c98b..eb4198b 100644
--- a/setup.py
+++ b/setup.py
@@ -29,11 +29,11 @@ setup(
     ],
     zip_safe=False,
     install_requires=[
-        'django',
-        'django-transmeta',
+        'django<2',
+        'django-transmeta-eh',
         'django-compat',
         'pyyaml',
-        'pyparsing'
+        'pyparsing',
         'six'
     ],
     setup_requires=[