def csv_file(tmp_path):
    """Generate a csv file for test purposes

    Args:
      tmp_path: temporary area to use to write files

    Returns:
      path to the csv file
    """
    tmp_path.mkdir(exist_ok=True)
    csv_file_path = tmp_path / "file.csv"
    csv_file_path.write_text("x,y\n0,0\n1,1\n")
    return csv_file_path