_____________________ TestInit.test_get_extension_by_flow _____________________
[gw3] win32 -- Python 3.5.6 c:\miniconda35-x64\python.exe
self = <tests.test_extensions.test_functions.TestInit testMethod=test_get_extension_by_flow>
    def test_get_extension_by_flow(self):
>       self.assertIsNone(get_extension_by_flow(DummyFlow()))
tests\test_extensions\test_functions.py:68: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
openml\extensions\functions.py:51: in get_extension_by_flow
    if extension_class.can_handle_flow(flow):
openml\extensions\sklearn\extension.py:75: in can_handle_flow
    return cls._is_sklearn_flow(flow)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
cls = <class 'openml.extensions.sklearn.extension.SklearnExtension'>
flow = <tests.test_extensions.test_functions.DummyFlow object at 0x000000AAB3AC3A58>
    @classmethod
    def _is_sklearn_flow(cls, flow: OpenMLFlow) -> bool:
>       if flow.dependencies is not None and "sklearn" in flow.dependencies:
E       AttributeError: 'DummyFlow' object has no attribute 'dependencies'
openml\extensions\sklearn\extension.py:493: AttributeError
============================== warnings summary ===============================
c:\miniconda35-x64\lib\genericpath.py:19