syntax_data: {"ast_node_type":"other","tokens":[{"end":47,"kind":"keyword","start":0,"text":"0x80..=0xff"}]}
source_snippet:             0x80..=0xff => use_punycode = true,
context_before:             b'_' | b'a'..=b'z' | b'A'..=b'Z' | b'0'..=b'9' => {}
context_after:             _ => bug!("symbol_names: bad byte {} in ident {:?}", b, ident),