code: public static Observable<? extends AVUser> signUpOrLoginByMobilePhoneInBackground(String mobilePhoneNumber, String smsCode) {
      return signUpOrLoginByMobilePhoneInBackground(mobilePhoneNumber, smsCode, internalUserClazz());
    }
docs: signUpOrLoginByMobilePhoneInBackground
  @param mobilePhoneNumber
  @param smsCode
  @return