code: def new_category(blog_id, username, password, category_struct):
      
      authenticate(username, password, 'zinnia.add_category')
      category_dict = {'title': category_struct['name'],
                       'description': category_struct['description'],
                       'slug': category_struct['slug']}
      if int(category_struct['parent_id']):
          category_dict['parent'] = Category.objects.get(
              pk=category_struct['parent_id'])
      category = Category.objects.create(**category_dict)
  
      return category.pk
docs: wp.newCategory(blog_id, username, password, category)
      => category_id