def METHOD_NAME(self, file=None):
    """Print some summary info to stdout."""
    if not file:
        file = sys.stdout
    print(f"HDU_CLASS = {self.hdu_class}", file=file)
    print(f"BASE_DIR = {self.base_dir}", file=file)
    print(f"FILE_DIR = {self.file_dir}", file=file)
    print(f"FILE_NAME = {self.file_name}", file=file)
    print(f"HDU_NAME = {self.hdu_name}", file=file)