syntax_data: {"ast_node_type":"other","tokens":[{"end":64,"kind":"keyword","start":0,"text":"b'_'"}]}
source_snippet:             b'_' | b'a'..=b'z' | b'A'..=b'Z' | b'0'..=b'9' => {}
context_before:         match b {
context_after:             0x80..=0xff => use_punycode = true,