DOC: Change refs in docs from pandas.SparseArray to pandas.arrays.SparseArray
- [x ] closes #30642
- [ ] tests added / passed
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- [ ] passes `black pandas`
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- [ ] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
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- [x] whatsnew entry

Change all references in docs to use `arrays.SparseArray` rather than just `SparseArray`

In #30642 I think Jeff was proposing that accessing `pandas.SparseArray` from the top-level namespace emits a warning. > In #30642 I think Jeff was proposing that accessing `pandas.SparseArray` from the top-level namespace emits a warning.

Ah, that's a bigger change.  I will change all references to `pandas.SparseArray` in the code to `pandas.arrays.SparseArray` and add the deprecation warning to `pandas.__init__.py`
 It's probably worth discussing whether we actually want to do that for 1.0. I'm not sure if it's worth introducing that right now. @TomAugspurger Well, I have all the changes done and am about to commit.  I'll separate it to a different PR, so you can merge this one as is (with the doc changes), and then we can use the new PR to discuss whether we do all those changes. > It's probably worth discussing whether we actually want to do that for 1.0. I'm not sure if it's worth introducing that right now.

@TomAugspurger not sure what the issue is here. This makes things very consistent with other EA (I agree Categorical is still there, but this makes a good step). I like #30566 better than this. > I like #30566 better than this.

#30566 has everything this one does, so if we go forward with that, we can close this one. closing in favor of #30566 