{"ast_node_type":"variable","tokens":[{"end":60,"kind":"keyword","start":0,"text":"let"}]}
    let env_def_id = tcx.hir_get_parent_item(hir_ty.hir_id);
    // scope. This is derived from the enclosing item-like thing.
    collect::ItemCtxt::new(tcx, env_def_id.def_id)