Documation: copy documenation is lacking detail for when deep=False #19505
Description
The DataFrame.copy documentation (for pandas 0.22.0) states:
deep : boolean or string, default True Make a deep copy, including a copy of the data and the indices. With deep=False neither the indices or the data are copied. Note that when deep=True data is copied, actual python objects will not be copied recursively, only the reference to the object. This is in contrast to copy.deepcopy in the Standard Library, which recursively copies object data. Problem description
The documentation does not state what is copied when deep=False (it doesn't copy data, it doesn't copy indices, what does it copy then?).
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