syntax_data: {"ast_node_type":"other","tokens":[{"end":35,"kind":"keyword","start":0,"text":"writeln!(f,"}]}
source_snippet:         writeln!(f, "digraph {{")?;
context_before:     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
context_after:         writeln!(f, "    {:?} [shape = doublecircle]", self.start)?;