+ PYTHONPATH=. python2.7 -m testtools.run testtools.tests.test_suite
Tests running...
======================================================================
FAIL: testtools.tests.test_run.TestRun.test_run_list_failed_import
----------------------------------------------------------------------
Traceback (most recent call last):
  File "testtools/tests/test_run.py", line 178, in test_run_list_failed_import
    run.main, ['prog', 'discover', '-l', broken.package.base, '*.py'], out)
  File "testtools/testcase.py", line 420, in assertRaises
    self.assertThat(our_callable, matcher)
  File "testtools/testcase.py", line 433, in assertThat
    raise mismatch_error
MismatchError: <function main at 0x7fa258bd1d70> returned None

Ran 1209 tests in 1.109s