Page not found (404)

Request Method: GET
Request URL: http://mongolbooks.com/%D0%BC%D0%BE%D0%BD%D0%B3%D0%BE%D0%BB%D1%8B%D0%BD-%D1%85%D2%AF%D0%BD-%D0%B0%D0%BC%D1%8B%D0%BD-%D1%81%D1%8D%D1%82%D0%B3%D2%AF%D2%AF%D0%BB%D0%B8%D0%B9%D0%BD-%D1%88%D0%B8%D0%BD%D1%8D-%D0%B4%D1%83%D0%B3%D0%B0%D0%B0%D1%80%D1%82-%D0%B1%D2%AF%D1%82%D1%8D%D1%8D%D0%BB%D1%8D%D1%8D-%D0%B8%D1%80%D2%AF%D2%AF%D0%BB%D1%8D%D1%85%D0%B8%D0%B9%D0%B3-%D1%83%D1%80%D1%8C%D0%B6-%D0%B1%D0%B0%D0%B9%D0%BD%D0%B0/

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You're seeing this error because you have DEBUG = True in your Django settings file. Change that to False, and Django will display a standard 404 page.