Can't get state restoring running

[yanone]

I read the documentation, but it's not immediately clear to me what to do.

I have put together the following code from the examples. In reality, a TAN is only required for the transactions, not for the balance, so the first TAN query never executes. I want to achieve that I have to enter a TAN only every couple of months like how it works for my banking app, but I can't understand from the documentation how to save the state.

It's probably just a minor mistake. Please help.

def kontostand(failOnError=False):
 blz = "***"
 login = "***"
 key_id = f"{blz}.{login}"
 password = keyring.get_password("fints", key_id)
 if not password:
 password = getpass.getpass("PIN:")
 keyring.set_password("fints", key_id, password)

 # Restore state
 tan_data = None
 if os.path.exists("tan.data"):
 with open("tan.data", "rb") as f:
 tan_data = f.read()

 client = FinTS3PinTanClient(
 blz, # Your bank's BLZ
 login, # Your login name
 password, # Your banking PIN
 "https://fints1.atruvia.de/cgi-bin/hbciservlet",
 product_id="6151256F3D4F9975B877BD4A2", # https://community.home-assistant.io/t/fints-access-needs-product-id/322464/4
 from_data=tan_data,
 )

 minimal_interactive_cli_bootstrap(client)
 with client:
 # Since PSD2, a TAN might be needed for dialog initialization.
 # Let's check if there is one required
 if client.init_tan_response:
 if failOnError:
 raise Exception("A TAN is required. Run tan.py separately.")
 else:
 print("A TAN is required", client.init_tan_response.challenge)
 tan = input("Please enter TAN:")
 client.send_tan(client.init_tan_response, tan)

 # Fetch accounts
 accounts = client.get_sepa_accounts()
 balance = client.get_balance(accounts[0])

 transactions = client.get_transactions_xml(accounts[0])
 if isinstance(transactions, NeedTANResponse):
 print("Eine TAN wird benötigt!")
 print(transactions.challenge)
 tan = input("TAN:")
 transactions = client.send_tan(transactions, tan)

 client_data = client.deconstruct()

 # Save state
 with open("tan.data", "wb") as f:
 f.write(client_data)

 return balance.amount.amount, transactions