commit 1dc2f5b5b131c1bf6c0e89fa28ba8a785a5865d3
Author: Ondřej Nový <ondrej.novy@firma.seznam.cz>
Date:   Mon Jul 11 07:39:30 2016 +0200

    Use LooseVersion for NumPy version comparing
    
    Because NumPy is releasing version likes 1.11.1rc1, which is not
    StrictVersion

diff --git a/pint/testsuite/helpers.py b/pint/testsuite/helpers.py
index 6b63d8f..5553647 100644
--- a/pint/testsuite/helpers.py
+++ b/pint/testsuite/helpers.py
@@ -4,7 +4,7 @@ from __future__ import division, unicode_literals, print_function, absolute_impo
 
 
 import doctest
-from distutils.version import StrictVersion
+from distutils.version import LooseVersion
 import re
 
 from pint.compat import unittest, HAS_NUMPY, HAS_UNCERTAINTIES, NUMPY_VER, PYTHON3
@@ -13,13 +13,13 @@ from pint.compat import unittest, HAS_NUMPY, HAS_UNCERTAINTIES, NUMPY_VER, PYTHO
 def requires_numpy18():
     if not HAS_NUMPY:
         return unittest.skip('Requires NumPy')
-    return unittest.skipUnless(StrictVersion(NUMPY_VER) >= StrictVersion('1.8'), 'Requires NumPy >= 1.8')
+    return unittest.skipUnless(LooseVersion(NUMPY_VER) >= LooseVersion('1.8'), 'Requires NumPy >= 1.8')
 
 
 def requires_numpy_previous_than(version):
     if not HAS_NUMPY:
         return unittest.skip('Requires NumPy')
-    return unittest.skipUnless(StrictVersion(NUMPY_VER) < StrictVersion(version), 'Requires NumPy < %s' % version)
+    return unittest.skipUnless(LooseVersion(NUMPY_VER) < LooseVersion(version), 'Requires NumPy < %s' % version)
 
 
 def requires_numpy():