Traceback (most recent call last):
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/bin/pytest", line 10, in <module>
    sys.exit(main())
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/_pytest/config/__init__.py", line 58, in main
    config = _prepareconfig(args, plugins)
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/_pytest/config/__init__.py", line 196, in _prepareconfig
    pluginmanager=pluginmanager, args=args
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/pluggy/hooks.py", line 289, in __call__
    return self._hookexec(self, self.get_hookimpls(), kwargs)
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/pluggy/manager.py", line 87, in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/pluggy/manager.py", line 81, in <lambda>
    firstresult=hook.spec.opts.get("firstresult") if hook.spec else False,
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/pluggy/callers.py", line 203, in _multicall
    gen.send(outcome)
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/_pytest/helpconfig.py", line 93, in pytest_cmdline_parse
    config = outcome.get_result()
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/pluggy/callers.py", line 80, in get_result
    raise ex[1].with_traceback(ex[2])
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/pluggy/callers.py", line 187, in _multicall
    res = hook_impl.function(*args)
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/_pytest/config/__init__.py", line 675, in pytest_cmdline_parse
    self.parse(args)
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/_pytest/config/__init__.py", line 845, in parse
    self._preparse(args, addopts=addopts)
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/_pytest/config/__init__.py", line 799, in _preparse
    self.pluginmanager.load_setuptools_entrypoints("pytest11")
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/pluggy/manager.py", line 292, in load_setuptools_entrypoints
    plugin = ep.load()
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/importlib_metadata/__init__.py", line 90, in load
    module = import_module(match.group('module'))
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 986, in _gcd_import
  File "<frozen importlib._bootstrap>", line 969, in _find_and_load
  File "<frozen importlib._bootstrap>", line 958, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 664, in _load_unlocked
  File "<frozen importlib._bootstrap>", line 634, in _load_backward_compatible
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/_pytest/assertion/rewrite.py", line 294, in load_module
    six.exec_(co, mod.__dict__)
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/pytest_postgresql/plugin.py", line 21, in <module>
    from pytest_postgresql import factories
  File "<frozen importlib._bootstrap>", line 969, in _find_and_load
  File "<frozen importlib._bootstrap>", line 958, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 664, in _load_unlocked
  File "<frozen importlib._bootstrap>", line 634, in _load_backward_compatible
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/_pytest/assertion/rewrite.py", line 294, in load_module
    six.exec_(co, mod.__dict__)
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/pytest_postgresql/factories.py", line 33, in <module>
    from pytest_postgresql.executor import PostgreSQLExecutor
  File "<frozen importlib._bootstrap>", line 969, in _find_and_load
  File "<frozen importlib._bootstrap>", line 958, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 664, in _load_unlocked
  File "<frozen importlib._bootstrap>", line 634, in _load_backward_compatible
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/_pytest/assertion/rewrite.py", line 294, in load_module
    six.exec_(co, mod.__dict__)
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/pytest_postgresql/executor.py", line 25, in <module>
    from mirakuru import TCPExecutor
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/mirakuru/__init__.py", line 23, in <module>
    from mirakuru.base import Executor, SimpleExecutor
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/mirakuru/base.py", line 83, in <module>
    class SimpleExecutor:  # pylint:disable=too-many-instance-attributes
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/site-packages/mirakuru/base.py", line 170, in SimpleExecutor
    exc_type: Optional[Type[BaseException]],
  File "/usr/lib/python3.5/typing.py", line 649, in __getitem__
    return Union[arg, type(None)]
  File "/usr/lib/python3.5/typing.py", line 552, in __getitem__
    dict(self.__dict__), parameters, _root=True)
  File "/usr/lib/python3.5/typing.py", line 512, in __new__
    for t2 in all_params - {t1} if not isinstance(t2, TypeVar)):
  File "/usr/lib/python3.5/typing.py", line 512, in <genexpr>
    for t2 in all_params - {t1} if not isinstance(t2, TypeVar)):
  File "/usr/lib/python3.5/typing.py", line 1077, in __subclasscheck__
    if super().__subclasscheck__(cls):
  File "/home/twitu/Code/swh-environment/swh-indexer/.tox/py3/lib/python3.5/abc.py", line 225, in __subclasscheck__
    for scls in cls.__subclasses__():
TypeError: descriptor '__subclasses__' of 'type' object needs an argument