# gdtest_sphinx_mixed_roles > Test mixed Sphinx role rendering ## Docs ### API Reference #### Classes > Main classes provided by the package - [Registry](reference/Registry.html): A registry that maps names to types #### Functions > Utility functions - [lookup](reference/lookup.html): Look up a type in the default :py:class:`Registry` - [register](reference/register.html): Register a type in the default :py:class:`Registry` - [validate_entry](reference/validate_entry.html): Validate a registry entry dict