syntax_data: {"ast_node_type":"other","tokens":[{"end":7,"kind":"keyword","start":0,"text":")"}]}
source_snippet:     ) {
context_before:         mut encode_expn: impl FnMut(&mut T, ExpnId, &ExpnData, ExpnHash),
context_after:         // When we serialize a `SyntaxContextData`, we may end up serializing