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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_nodes(self, request):
 """ Return menu's node for categories """

        nodes = []
        nodes.append(NavigationNode(_('Categories'),
                                    reverse('zinnia:category_list'),
                                    'categories'))
        for category in Category.objects.all():
            nodes.append(NavigationNode(category.title,
                                        category.get_absolute_url(),
                                        category.pk, 'categories'))
        return nodes