def METHOD_NAME(self, filename, filename_info, filetype_info):
    """Mimic reader input file content."""
    num_scans = 20
    num_cols = 2048
    global_attrs = {
        '/attr/timestamp_without_timezone': '2022-01-13T12:45:00',
        '/attr/satellite_observation_point_height': '38500.0',
        '/attr/satellite_observation_point_latitude': '71.25',
        '/attr/satellite_observation_point_longitude': '21.44',
    }
    data = self._get_data(num_scans, num_cols)
    test_content = {}
    test_content.update(global_attrs)
    test_content.update(data)
    return test_content