syntax_data: {"ast_node_type":"other","tokens":[{"end":60,"kind":"keyword","start":0,"text":"instrument_mcount:"}]}
source_snippet:     instrument_mcount: bool = (false, parse_bool, [TRACKED],
context_before:         "print some statistics about AST and HIR (default: no)"),
context_after:         "insert function instrument code for mcount-based tracing (default: no)"),