Page not found (404)

Request Method: GET
Request URL: http://mongolbooks.com/%D1%8D%D0%BA%D0%BE%D0%BB%D0%BE%D0%B3%D0%B8-%D1%8D%D0%B2%D0%BE%D0%BB%D1%8E%D1%86%D0%B8%D0%B9%D0%BD-%D0%BD%D1%8D%D1%80-%D1%82%D0%BE%D0%BC%D1%8C%D1%91%D0%BE%D0%BD%D1%8B-%D0%B0%D0%BD%D0%B3%D0%BB%D0%B8-%D0%BC%D0%BE%D0%BD%D0%B3%D0%BE%D0%BB-%D1%82%D0%B0%D0%B9%D0%BB%D0%B1%D0%B0%D1%80-%D1%82%D0%BE%D0%BB%D1%8C/

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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.