syntax_data: {"ast_node_type":"other","tokens":[{"end":53,"kind":"keyword","start":0,"text":"foreign_expn_hashes:"}]}
source_snippet:     foreign_expn_hashes: FxHashMap<ExpnId, ExpnHash>,
context_before:     foreign_expn_data: FxHashMap<ExpnId, ExpnData>,
context_after:     expn_hash_to_expn_id: UnhashMap<ExpnHash, ExpnId>,