def find_categories(categories, parent=None):
for category_config in raw_categories:
yield Category(id=category_config['id'],
name=category_config['name'],
parent=parent)
for subcategory_config in category_config.get('subcategories', []):
yield Category(id=subcategory_config['id'],
name=subcategory_config['name'],
parent=category_config['id'])
