code: def _normalize_images(self):
          
          if 'image' not in self.data:
              return
          for img in self.data['image']:
              fname = img['file'].replace('_', ' ')
              fstart = fname.startswith('File:')
              istart = fname.startswith('Image:')
              if not fstart and not istart:
                  fname = 'File:' + fname
                  img['orig'] = img['file']
                  img['file'] = fname
docs: normalizes image filenames by prepending 'File:' if needed