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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def save_calibration(labware: Labware, delta: Point):
 """ Function to be used whenever an updated delta is found for the first well of a given labware. If an offset file does not exist, create the file using labware id as the filename. If the file does exist, load it and modify the delta and the lastModified fields under the "default" key. """

    calibration_path = CONFIG['labware_calibration_offsets_dir_v4']
    if not calibration_path.exists():
        calibration_path.mkdir(parents=True, exist_ok=True)
    labware_offset_path = calibration_path/'{}.json'.format(labware._id)
    calibration_data = _helper_offset_data_format(
        str(labware_offset_path), delta)
    with labware_offset_path.open('w') as f:
        json.dump(calibration_data, f)
    labware.set_calibration(delta)