code: def watermark(url, args=''):
      
      # initialize some variables
      args = args.split(',')
  
      params = dict(
          name=args.pop(0),
          opacity=0.5,
          tile=False,
          scale=1.0,
          greyscale=False,
          rotation=0,
          position=None,
          quality=QUALITY,
          obscure=OBSCURE_ORIGINAL,
          random_position_once=RANDOM_POSITION_ONCE,
      )
  
      params['url'] = unquote(url)
  
      # iterate over all parameters to see what we need to do
      for arg in args:
          key, value = arg.split('=')
          key, value = key.strip(), value.strip()
          if key == 'position':
              params['position'] = value
          elif key == 'opacity':
              params['opacity'] = utils._percent(value)
          elif key == 'tile':
              params['tile'] = bool(int(value))
          elif key == 'scale':
              params['scale'] = value
          elif key == 'greyscale':
              params['greyscale'] = bool(int(value))
          elif key == 'rotation':
              params['rotation'] = value
          elif key == 'quality':
              params['quality'] = int(value)
          elif key == 'obscure':
              params['obscure'] = bool(int(value))
          elif key == 'random_position_once':
              params['random_position_once'] = bool(int(value))
  
      return Watermarker()(**params)
docs: Returns the URL to a watermarked copy of the image specified.