from deltalake import DeltaTable
import pandas as pd


@transformer
def transform(magic_energy, *args, **kwargs):
    dt = DeltaTable(
        # Change this to your unique URI from a previous step
        # if you’re using your own AWS credentials.
        's3://mage-demo-public/battle-history/1337',
        storage_options={
            'AWS_ACCESS_KEY_ID': '...',
            'AWS_SECRET_ACCESS_KEY': '...',
        },
    )
    battle_history = dt.to_pandas()

    return pd.concat([magic_energy, battle_history])