Python Skript kann keine Daten in mysql einfügen

import Adafruit_DHT
import time 
import MySQLdb

from datetime import datetime
 
sensor = Adafruit_DHT.DHT22
 
# 1-Wire-Pin. BCM-Bezeichnung nutzen!
pin = 4
while True:
    humidity, temperature = Adafruit_DHT.read(sensor, pin)
    if humidity is not None and temperature is not None:
        #Sensordaten abfragen
        f = open('log.txt', 'a')  
        f.write('Temp={0:0.1f}*C'.format(temperature))  
        f.write(' ')  

        f.write('Humidity={0:0.1f}%'.format(humidity))  
        f.write(' ')  
        f.write(datetime.now().strftime('%Y-%m-%d %H:%M:%S'))  
        f.write('\n')  
        f.close()
        #Verbindung zum mySQL-Server und Datensatz eintragen
        connection = MySQLdb.connect(host = "ip-adresse",  
                                       db = "datenbank",  
                                     user = "root",  
                                   passwd = "toor")  
        cursor = connection.cursor()
        print temperature
        print humidity
        cursor.execute("INSERT INTO daten (sender_id, temperature, humidity) VALUES (1, temperature, humidity)" )  
        print  temperature
        print  humidity
        cursor.close()
        cursor.commit()
        time.sleep(60)
    else:
        print "Lesefehler. Erneut versuchen!"  
        time.sleep(2)