Problem: dynamically created data containers have bad base classes

[mehdisadeghi]

Any class created with create_data_container helper function, which is supposed to be subclass of DataContainer, will not pass the following check:

DC = create_data_container()
dc = DC()
isinstance(dc, DataContainer) # False

Solution: add __bases__ attribute to the created classes

[codecov-io]

Current coverage is 72.04% (diff: 100%)

Merging #319 into master will not change coverage

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[itziakos]

I do not think that there is a need for the check isinstance(DataContainers). It is actualy wrong to do so since wrapper engines could have their own implementation of the DataContainer object. The important thing is to support the api for all CUDS objects as described in the docs.

Furthermore, manually manipulating __base__ is beyond bad. If the need for an isinstance check is anavoidable the we need to have ABCDataContainer where compatible classes will register themselves and then isinstance(ABCDataContainer) will be true.

[itziakos]

Furthermore, manually manipulating __base__ is beyond bad

Hmm.. I missed the fact that you are already creating a class at runtime. However, looking at the code DataContainer should be already part of the base classes since the type function should have done it for you.

[mehdisadeghi]

DataContainer should be already part of the base classes since the type function should have done it for you

Strange. On my system it didn't work without explicitly setting __bases__. I'll double check if I'm missing something.

[itziakos]

I think that there is a confusion. The result of the create_data_container is a class type. when checking with isinstance you should check with result()

[mehdisadeghi]

you should check with result()

I checked with the instance. However, as you referenced the type doc, it should be already done by setting the bases tuple. I have definitely made a mistake during my debug. I'll probably close this PR.

[itziakos]

I have definitely made a mistake during my debug.

Yes I wanted to say that the instance, class type confusion could be done during the debug session.

[mehdisadeghi]

This PR is misleading, I close it.