HBase unittest fails when using python 2.6

[root@c6401 ambari-server]# python
Python 2.6.6 (r266:84292, Jul 23 2015, 15:22:56)
[GCC 4.4.7 20120313 (Red Hat 4.4.7-11)] on linux2
Type "help", "copyright", "credits" or "license" for more information.

[root@c6401 ambari-server]# mvn test
.
.
.
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Failed tests:
ERROR: Failed to load test files ['test_phoenix_queryserver', 'test_hbase_master', 'test_hbase_client', 'test_hbase_service_check', 'test_hbase_regionserver']
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Traceback (most recent call last):
  File "unitTests.py", line 120, in stack_test_executor
    modules]
  File "/usr/lib64/python2.6/unittest.py", line 575, in loadTestsFromName
    module = __import__('.'.join(parts_copy))
  File "/root/ambari/ambari-server/src/test/python/stacks/2.0.6/HBASE/test_phoenix_queryserver.py", line 21, in <module>
    from unittest import SkipTest
ImportError: cannot import name SkipTest

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