def __init__(self, cache_dir_url, file_urls, dataset_size):
        """
        :param cache_dir_url: A string denoting the path to store the cache files.
        :param file_urls: a list of parquet file url list of this dataset.
        :param dataset_size: An int denoting the number of rows in the dataframe.
        """
        self.cache_dir_url = cache_dir_url
        self.file_urls = file_urls
        self.dataset_size = dataset_size

        :param cache_dir_url: A string denoting the path to store the cache files.
        :param file_urls: a list of parquet file url list of this dataset.
        :param dataset_size: An int denoting the number of rows in the dataframe.
        
petastorm/spark/spark_dataset_converter.py