text: import copy
  from .augmenter import Augmenter
  
  class RoiExtractor(Augmenter):
    '''
    Augmenter that extracts the ROI from the image and returns
    that as a new SampleImage.
    '''
    def augment(self, sample):
      _, _, w, h = sample.roi
      sample_copy = copy.copy(sample)
  
      sample_copy.image = sample.roi_image
      sample_copy.roi = (0, 0, w, h)
  
      return sample_copy
  