syntax_data: {"ast_node_type":"other","tokens":[{"end":89,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:         // These lang items are not actually defined in core/std. Experiment is a part of
context_before:         // Lang items which are used only for experiments with auto traits with default bounds.
context_after:         // `MCP: Low level components for async drop`(https://github.com/rust-lang/compiler-team/issues/727)