--- a/src/ast_dump.rs
+++ b/src/ast_dump.rs
@@ -272,9 +272,10 @@ impl stmt {
                     statements_to_string(indent, body)
                 )
             },
-            stmt::FunctionDef(name, arguments, body, decorator_list, returns) => {
-                format!("{}{}def {}({}){}:\n{}",
+            stmt::FunctionDef(name, arguments, body, decorator_list, returns, async) => {
+                format!("{}{}{}def {}({}){}:\n{}",
                     decorator_list_to_string(decorator_list, indent),
+                    if async { "async " } else { "" },
                     current_indent,
                     name,
                     arguments.to_string(),