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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def logout(self):
 """ View function to log a user out. Supports html and json requests. """

        if current_user.is_authenticated:
            self.security_service.logout_user()

        if request.is_json:
            return '', HTTPStatus.NO_CONTENT

        self.flash(_('flask_unchained.bundles.security:flash.logout'),
                   category='success')
        return self.redirect('SECURITY_POST_LOGOUT_REDIRECT_ENDPOINT')