syntax_data: {"ast_node_type":"other","tokens":[{"end":22,"kind":"keyword","start":0,"text":"tcx:"}]}
source_snippet:     tcx: TyCtxt<'tcx>,
context_before: fn type_op_normalize_poly_fn_sig<'tcx>(
context_after:     canonicalized: CanonicalQueryInput<'tcx, ParamEnvAnd<'tcx, Normalize<PolyFnSig<'tcx>>>>,