Python Çalışmayı Durdurdu

import sys
import sqlite3

from PyQt5 import QtWidgets

class Window(QtWidgets.QWidget):

    def __init__(self):

        super().__init__()
        self.create_connect()
        self.init_ui()

    def create_connect(self):
        self.con = sqlite3.connect("kullanıcı_verileri.db")
        self.cursor = self.con.cursor()

        query = "Create table if not exists database (nickname TEXT, password TEXT)"

        self.cursor.execute(query)
        self.con.commit()

    def init_ui(self):

        self.welcome = QtWidgets.QLabel("Programa Hoşgeldiniz.")
        self.nickname_area = QtWidgets.QLineEdit("")
        self.password_area = QtWidgets.QLineEdit("")
        self.password_area.setEchoMode(QtWidgets.QLineEdit.Password)
        self.loginbutton = QtWidgets.QPushButton("Giriş Yap")
        self.registerbutton = QtWidgets.QPushButton("Kayıt Ol")

        v_box = QtWidgets.QVBoxLayout()

        v_box.addWidget(self.welcome)
        v_box.addWidget(self.nickname_area)
        v_box.addWidget(self.password_area)
        v_box.addStretch()
        v_box.addWidget(self.loginbutton)
        v_box.addWidget(self.registerbutton)

        h_box = QtWidgets.QHBoxLayout()

        h_box.addStretch()
        h_box.addLayout(v_box)
        h_box.addStretch()


        self.setLayout(h_box)
        self.setWindowTitle("Kullanıcı Girişi")

        self.loginbutton.clicked.connect(self.login)
        self.registerbutton.clicked.connect(self.register)

        self.show()

    def login(self):

        nickname = self.nickname_area.text()
        password = self.password_area.text()

        query = "Select * from database where nickname = ? and where password = ?"

        self.cursor.execute(query,(nickname,password))
        data = self.cursor.fetchall()

        if len(data) == 0:
            self.welcome.setText("Böyle bir kullanıcı yok\n Lütfen Tekrar Deneyiniz.")
        else:
            self.welcome.setText("Hoşgeldiniz." + nickname)




    def register(self):

        nickname = self.nickname_area.text()
        password = self.password_area.text()

        query = "Insert into database Values (?,?)"

        self.cursor.execute(query,(nickname,password))
        self.con.commit()

        self.welcome.setText("Başarıyla kayıt olundu.")



app = QtWidgets.QApplication(sys.argv)
window = Window()
sys.exit(app.exec())

  self.cursor.execute(query,(nickname,password))
sqlite3.OperationalError: near "where": syntax error

#2 adet where
query = "Select * from database where nickname = ? and where password = ?"
#Doğru yazımı
query = "Select * from database where nickname = ? and password = ?"