from collections.abc import Iterator
VALID_HTML_CONTEXTS: dict[tuple[str, str], str] = {
# https://html.spec.whatwg.org/multipage/indices.html#elements-3
("a", "phrasing"): "transparent",
("abbr", "phrasing"): "phrasing",
("address", "flow"): "flow",
("area", "phrasing"): "void",
("article", "flow"): "flow",
("aside", "flow"): "flow",
("audio", "phrasing"): "