'Return a context manager for an indexing mode.
Parameters
mode : str
Either \'freeze\', \'copy_on_getitem\', or \'discard_on_copy\'.
In \'discard_on_copy\' mode,
indices are not copied whenever columns or tables are copied.
In \'freeze\' mode, indices are not modified whenever columns are
modified; at the exit of the context, indices refresh themselves
based on column values. This mode is intended for scenarios in
which one intends to make many additions or modifications in an
indexed column.
In \'copy_on_getitem\' mode, indices are copied when taking column
slices as well as table slices, so col[i0:i1] will preserve
indices.'

def index_mode(self, mode):

    return _IndexModeContext(self, mode)
