Index.ndim return the number of dimensions of the underlying data, by definition 1

Index.symmetric_difference(other, result_name=None)

Index.base return the base object if the memory of the underlying data is shared

Index.to_series(**kwargs)

Index.get_indexer(target, method=None, limit=None, tolerance=None)

Index.sym_diff(*args, **kwargs)

Index.dtype = None

Index.union(other)

class pandas.Index

Index.append(other)