fix openhab error: Rule ‘[rulename]’: An error occurred during the script execution: index=0, size=0

My goal is to execute an python-script when the Battery-charge has reached 70% My rule was not executed, the error as shown above is seen in the log.My faulty script: Reason of the error: the if-statement is misleading, to check if the value is equal it needs two “==”: working-code: to debug BYDBat/KOSTALPLENTICOREPlus70WithBattery_BatteryCharge.state debugging needs