--- a/src/ast_convert.rs
+++ b/src/ast_convert.rs
@@ -564,13 +564,14 @@ fn parse_statement(py: Python, ast: PyOb
         let name = ast.getattr(py, "name").unwrap();
         let args = ast.getattr(py, "args").unwrap();
         let body = ast.getattr(py, "body").unwrap();
+        let returns = ast.getattr(py, "returns").unwrap();
 
         let name = get_str(py, name);
         let args = parse_arguments(py, args);
         let body = parse_list(py, body, parse_statement);
 
         let decorators = vec!();
-        let returns = None;
+        let returns = parse_optional_expr(py, returns);
 
         stmt::FunctionDef(name, args, body, decorators, returns)
     } else if is_instance(&ast, &global_type) {