There is also Parser.html_entities, Parser.html_entity_parser, Parser.parse_html_entities and Parser.encode_html_entities.
I recently wanted to move away URI variable fiddling from Protocols.HTTP into Standards.URI, since Standards.URI is used anyway. When I had added get_query_variables, set_query_variables, add_query_variable and add_query_variables then problem of where the encoding should be arised, so I didn't check anything in.