import mysql.connector

cnx = mysql.connector.connect(user='root', password='',
                              host='localhost',
                              database='pythonn')

cursor = cnx.cursor()

name = input('Wpisz imie: ')
surname = input('Wpisz nazwisko: ')
cost = input('Wpisz dlug: ')

cursor.execute("INSERT INTO dluznicy VALUES (" + null + "," + name + "," + surname + "," + cost + ")")

cnx.commit()

cursor.close()
cnx.close()