code

import MySQLdb
from tkinter import *

root = Tk()

def makeLoggedInWindow():
    if(query.execute("SELECT * FROM 'USERS' where 'username'", 'username',  "' AND `password`='", 'password', "'")):
        window = Tk()
        db.commit()
        label_3 = Label(window, text="Du er nu logget ind!")
        label_3.pack()
    else:
        db.commit()
        print ("Login fejlede!")

label = Label(root, text="Velkommen til mit log ind script!")
db = MySQLdb.connect(host="localhost",
                     user="root",
                     db="users")

query = db.cursor()

loop = 'true'
label_1 = Label(root, text="Username: ")
label_2 = Label(root, text="Password: ")
username = Entry(root)
password = Entry(root, show='*')
button_1 = Button(root, text="Log ind!", command=makeLoggedInWindow)

label_1.pack()
label_2.pack()
username.pack()
password.pack()
button_1.pack()

root.mainloop()