Dataframe.sparse and Series.sparse property accessors are not implemented

[gshimansky]

System information

• OS Platform and Distribution (e.g., Linux Ubuntu 16.04):

Ubuntu 20.04

• Modin version (modin.__version__):

0.7.3+110.g6637572

• Python version:

Python 3.8.2

• Code we can use to reproduce:

Describe the problem

sparse property accessor should allow access to .density property and .from_spmatrix, .to_coo, .to_dense functions. See https://pandas.pydata.org/pandas-docs/stable/reference/frame.html#api-frame-sparse

Source code / logs

[dchigarev]

All sparse accessors were added in #2318, however all of them are defaulting to pandas

[pyrito]

Trying this on latest master and it seems that the property accessors are implemented now, but as @dchigarev they are defaulting to pandas. I think the main issue here has been resolved, so I'm going to close this issue.