Failing tests on xenial

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FAIL: test_CONTAINSSTRING (tests.sqlobject.SQLObjectTest)
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Traceback (most recent call last):
  File "/home/ubuntu/src/storm-trunk/tests/mocker.py", line 102, in test_method_wrapper
    result = test_method()
  File "/home/ubuntu/src/storm-trunk/tests/sqlobject.py", line 1213, in test_CONTAINSSTRING
    ["John Doe"])
AssertionError: Lists differ: [] != ['John Doe']

Second list contains 1 additional elements.
First extra element 0:
John Doe

- []
+ ['John Doe']

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FAIL: test_selectFirst (tests.sqlobject.SQLObjectTest)
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Traceback (most recent call last):
  File "/home/ubuntu/src/storm-trunk/tests/mocker.py", line 102, in test_method_wrapper
    result = test_method()
  File "/home/ubuntu/src/storm-trunk/tests/sqlobject.py", line 349, in test_selectFirst
    self.assertNotEqual(person, None)
AssertionError: None == None

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Ran 2673 tests in 27.872s