Merge pull request matplotlib#2879 from tacaswell/six_version

BLD : adjust min six version to 1.3

Author: efiring

lib/matplotlib/__init__.py

@@ -126,9 +126,9 @@ def compare_versions(a, b):
     else:
         return False
 
-if not compare_versions(six.__version__, '1.5'):
+if not compare_versions(six.__version__, '1.3'):
     raise ImportError(
-        'six 1.5 or later is required; you have %s' % (
+        'six 1.3 or later is required; you have %s' % (
             six.__version__))
 
 try:

setupext.py

@@ -1090,7 +1090,7 @@ def get_extension(self):
 
 class Six(SetupPackage):
     name = "six"
-    min_version = "1.5"
+    min_version = "1.3"
 
     def check(self):
         try: