def create_seq_db(data):
    """Convert interactions of a user to a sequence.

    Args:
        data (pandas.DataFrame): The dataset to be transformed.

    Returns:
        result (pandas.DataFrame): Transformed dataset with "col_user" and "col_sequence".
    """
    # group by user id and concat item id
    groups = data.groupby("col_user")

    # convert item ids to int, then aggregate them to lists
    aggregated = groups.col_item.agg(col_sequence=lambda x: list(map(int, x)))

    result = aggregated
    result.reset_index(inplace=True)
    return result