Try to fix up tests, Python 3.8 warnings

.travis.yml

@@ -1,8 +1,8 @@
 language: python
 python:
+  - '3.7'
   - '3.6'
   - '3.5'
-  - '3.4'
   - '2.7'
 services:
   - mysql

dataset/util.py

@@ -1,6 +1,10 @@
 import six
 from hashlib import sha1
-from collections import OrderedDict, Iterable
+try:
+    from collections.abc import Iterable
+except ImportError:
+    from collections as Iterable
+from collections import OrderedDict 
 from six.moves.urllib.parse import urlparse
 
 QUERY_STEP = 1000

test/test_dataset.py

@@ -1,3 +1,4 @@
+# coding: utf-8
 from __future__ import unicode_literals
 
 import os

tox.ini

@@ -0,0 +1,5 @@
+[tox]
+envlist = py27,py37
+[textenv]
+deps=nose
+commands=python setup.py test