{"ast_node_type":"variable","tokens":[{"end":62,"kind":"keyword","start":0,"text":"let"}]}
    let trait_ref_self = cx.tcx.erase_regions(trait_ref_self);
    let trait_ref_self = trait_ref.with_self_ty(cx.tcx, ty);
    let trait_def_id = trait_ref_self.def_id;