def parquet_to_df(filename, use_threads=1):
    """parquet_to_df: Reads a Parquet file into a Pandas DataFrame
        Args:
            filename (string): The full path to the filename for the Parquet file
            ntreads (int): The number of threads to use (defaults to 1)
    """
    try:
        return pq.read_table(filename, use_threads=use_threads).to_pandas()
    except pa.lib.ArrowIOError:
        print('Could not read parquet file {:s}'.format(filename))
        return None