def legacy(username, password)

  try:
      user = User.objects.get(username=username)
      if user.check_password(password):
        return user
      return None
  except User.DoesNotExist:
      user = fetch_user_from_legacy_db_if_password_is_correct(username, legacy)

      return User.objects.create_user(
          username=user.username,
          email=user.email,
          password=make_password(password),
          first_name=user.first_name[:30],
          last_name=user.last_name[:30],
      )