# Add topic column (categorical sampler)
dd.add_column(
    C.SamplerColumn(
        name="topic",
        type=P.SamplerType.CATEGORY,
        params=P.CategorySamplerParams(
            values=[
                "neural networks", "deep learning", "machine learning", "NLP",
                "computer vision", "reinforcement learning", "AI ethics", "data science"
            ]
        )
    )
)