I'd use a named tuple instead. This allows you to reference the mappings by name instead of index (`map[0]` isn't very clear about what you're mapping to/from).

Inside class definition before `__init__` add
`RenameMapping = namedtuple('RenameMapping ', ['integer', 'original'])`

Then `return RenameMapping(mapping_to_int, mapping_to_orig)` in the method

Also if you were returning just the two items, `return mapping_to_int, mapping_to_orig` would automatically convert to effectively return `tuple(mapping_to_int, mapping_to_orig)` without the need for brackets/parens.