diff --git a/scour/scour.py b/scour/scour.py
index a531795..8f32367 100644
--- a/scour/scour.py
+++ b/scour/scour.py
@@ -44,31 +44,30 @@
 # - parse transform attribute
 # - if a <g> has only one element in it, collapse the <g> (ensure transform, etc are carried down)
 
-# necessary to get true division
-from __future__ import division
 
-# Needed for Python 2/3 compatible print function.
-from __future__ import print_function
-from __future__ import absolute_import
+from __future__ import division         # use "true" division instead of integer division in Python 2 (see PEP 238)
+from __future__ import print_function   # use print() as a function in Python 2 (see PEP 3105)
+from __future__ import absolute_import  # use absolute imports by default in Python 2 (see PEP 328)
 
-import os
-import sys
-import xml.dom.minidom
-import re
 import math
-import time
-from collections import namedtuple
-from scour.svg_regex import svg_parser
-from scour.svg_transform import svg_transform_parser
 import optparse
-from scour.yocto_css import parseCssString
-import six
-from six.moves import range
+import os
+import re
+import sys
+import time
+import xml.dom.minidom
+from collections import namedtuple
 from decimal import Context, Decimal, InvalidOperation, getcontext
 
+import six
+from six.moves import range
 
+from scour.svg_regex import svg_parser
+from scour.svg_transform import svg_transform_parser
+from scour.yocto_css import parseCssString
 from scour import __version__
 
+
 APP = u'scour'
 VER = __version__
 COPYRIGHT = u'Copyright Jeff Schiller, Louis Simard, 2010'
diff --git a/scour/svg_regex.py b/scour/svg_regex.py
index 4cba554..0926363 100644
--- a/scour/svg_regex.py
+++ b/scour/svg_regex.py
@@ -47,6 +47,7 @@ import re
 from decimal import Decimal, getcontext
 from functools import partial
 
+
 # Sentinel.
 
 
diff --git a/scour/svg_transform.py b/scour/svg_transform.py
index 85bea88..944d34c 100644
--- a/scour/svg_transform.py
+++ b/scour/svg_transform.py
@@ -60,9 +60,10 @@ from __future__ import absolute_import
 
 import re
 from decimal import Decimal
-from six.moves import range
 from functools import partial
 
+from six.moves import range
+
 
 # Sentinel.
 class _EOF(object):
diff --git a/setup.py b/setup.py
index 3fe0831..5149e88 100644
--- a/setup.py
+++ b/setup.py
@@ -18,7 +18,8 @@
 
 import os
 import re
-from setuptools import setup, find_packages
+
+from setuptools import find_packages, setup
 
 LONGDESC = """
 Scour is a SVG optimizer/sanitizer that can be used to produce SVGs for Web deployment.
diff --git a/testscour.py b/testscour.py
index 1f5bbf9..cd0c59e 100755
--- a/testscour.py
+++ b/testscour.py
@@ -22,24 +22,23 @@
 
 from __future__ import absolute_import
 
+import unittest
+
 import six
 from six.moves import map, range
 
-import unittest
-
+from scour.scour import makeWellFormed, parse_args, scourString, scourXmlFile
 from scour.svg_regex import svg_parser
-from scour.scour import scourXmlFile, scourString, parse_args, makeWellFormed
 
 
 SVGNS = 'http://www.w3.org/2000/svg'
 
+
 # I couldn't figure out how to get ElementTree to work with the following XPath
 # "//*[namespace-uri()='http://example.com']"
 # so I decided to use minidom and this helper function that performs a test on a given node
 # and all its children
 # func must return either True (if pass) or False (if fail)
-
-
 def walkTree(elem, func):
     if func(elem) is False:
         return False