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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def login(self, username, password='', login_key=None, auth_code=None, two_factor_code=None, login_id=None):
 """Login as a specific user :param username: username :type username: :class:`str` :param password: password :type password: :class:`str` :param login_key: login key, instead of password :type login_key: :class:`str` :param auth_code: email authentication code :type auth_code: :class:`str` :param two_factor_code: 2FA authentication code :type two_factor_code: :class:`str` :param login_id: number used for identifying logon session :type login_id: :class:`int` :return: logon result, see `CMsgClientLogonResponse.eresult <https://github.com/ValvePython/steam/blob/513c68ca081dc9409df932ad86c66100164380a6/protobufs/steammessages_clientserver.proto#L95-L118>`_ :rtype: :class:`.EResult` .. note:: Failure to login will result in the server dropping the connection, ``error`` event is fired ``auth_code_required`` event is fired when 2FA or Email code is needed. Here is example code of how to handle the situation. .. code:: python @steamclient.on(steamclient.EVENT_AUTH_CODE_REQUIRED) def auth_code_prompt(is_2fa, code_mismatch):
 if is_2fa: code = input("Enter 2FA Code: ") steamclient.login(username, password, two_factor_code=code) else: code = input("Enter Email Code: ") steamclient.login(username, password, auth_code=code) Codes are required every time a user logins if sentry is not setup. See :meth:`set_credential_location` """

        self._LOG.debug("Attempting login")

        if not self._pre_login():
            return EResult.TryAnotherCM

        self.username = username

        message = MsgProto(EMsg.ClientLogon)
        message.header.steamid = SteamID(type='Individual', universe='Public')
        message.body.protocol_version = 65579
        message.body.client_package_version = 1771
        message.body.client_os_type = EOSType.Windows10
        message.body.client_language = "english"
        message.body.should_remember_password = True
        message.body.supports_rate_limit_response = True

        if login_id is None:
            message.body.obfustucated_private_ip = ip_to_int(self.connection.local_address) ^ 0xF00DBAAD
        else:
            message.body.obfustucated_private_ip = login_id

        message.body.account_name = username

        if login_key:
            message.body.login_key = login_key
        else:
            message.body.password = password

        sentry = self.get_sentry(username)
        if sentry is None:
            message.body.eresult_sentryfile = EResult.FileNotFound
        else:
            message.body.eresult_sentryfile = EResult.OK
            message.body.sha_sentryfile = sha1_hash(sentry)

        if auth_code:
            message.body.auth_code = auth_code
        if two_factor_code:
            message.body.two_factor_code = two_factor_code

        self.send(message)

        resp = self.wait_msg(EMsg.ClientLogOnResponse, timeout=30)

        if resp and resp.body.eresult == EResult.OK:
            self.sleep(0.5)

        return EResult(resp.body.eresult) if resp else EResult.Fail