Support hierarchies in get_elements_dataframe

[MariusWirtz]

Fixes #868

[MariusWirtz]

@Sven-Bo this should resolve the issue #868
please upgrade to this branch and verify that it resolves the issue

pip uninstall tm1py
pip install https://github.com/cubewise-code/tm1py/archive/refs/heads/master.zip

On a side note, the tm1.power_bi.get_member_properties is actually just a pointer to the tm1.elements.get_elements_dataframe function. Just like the tm1.power_bi.execute_mdx points to the tm1.cells.execute_mdx_dataframe_shaped.

Lots of users get confused about the PowerBiService within TM1py. While it actually just delegates to other functions, within TM1py, I wonder if we might deprecate it in a future version and ask people to call the underlying functions directly.

df = tm1.elements.get_elements_dataframe(
    dimension_name="TM1py Region",
    hierarchy_name="TM1py City",
    skip_weights=False)

	TM1py Region	Type	Currency	level000_Weight	level000
0	Munich	Numeric		1	Germany

[Sven-Bo]

@MariusWirtz , thank you so much for the prompt fix! Upgrading to the latest branch did the trick, and everything is now working perfectly.

I also appreciate the heads up about the PowerBIService simply being a pointer to other methods. I had actually noticed this myself while I was digging around, trying to understand what was happening behind the scenes.

Regarding your suggestion to deprecate the PowerBiService, I personally don't find it confusing, but I wouldn't mind calling the underlying functions either. Whatever makes things simpler and more efficient.

Once again, thanks for your help in resolving the issue.

[MariusWirtz]

Thanks!