Sort object by labels (along an axis).
The axis along which to sort. The value 0 identifies the rows,
and 1 identifies the columns.
If not None, sort on values in specified index level(s).
Sort ascending vs. descending.
If True, perform operation in-place.
Choice of sorting algorithm. See also ndarray.np.sort for more
information. mergesort is the only stable algorithm. For
DataFrames, this option is only applied when sorting on a single
column or label.
Puts NaNs at the beginning if first; last puts NaNs at the end.
Not implemented for MultiIndex.
If True and sorting by level and index is multilevel, sort by other
levels too (in order) after sorting by specified level.
If True, the resulting axis will be labeled 0, 1, …, n - 1.
New in version 1.0.0.
DataFrame with sorted index if inplace=False, None otherwise.