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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 get_admin_urls_for_registration(self):
 """ Utilised by Wagtail's 'register_admin_urls' hook to register urls for used by any associated ModelAdmin instances """

        urls = []
        for instance in self.modeladmin_instances:
            urls.extend(instance.get_admin_urls_for_registration())
        return urls