Either<String, Unit> fetchData() {
  // Simulate a successful API call
  int statusCode = 200;

  if (statusCode == 200) {
    // If the status code is 200, return Unit to represent success
    return right(unit);
  } else {
    // Otherwise, return a failure message
    return left('Error: Failed to fetch data');
  }
}

void main() {
  // Call the fetchData function and handle the Either result
  fetchData().fold(
    (failure) => print(failure),
    (unit) => print('Data fetched successfully'),
  );
}