          out << "  " << messaget::red << step.comment << messaget::reset << '\n';          if(step.pc->is_assert())         {           out << "  "               << from_expr(ns, step.function_id, step.pc->get_condition())               << '\n';         }          out << '\n';       }       break;      case goto_trace_stept::typet::ASSUME:     