code: def active_thresholds_value_maps(keywords, exposure_key):
      
      if 'classification' in keywords:
          if keywords['layer_mode'] == layer_mode_continuous['key']:
              return keywords['thresholds']
          else:
              return keywords['value_map']
      if keywords['layer_mode'] == layer_mode_continuous['key']:
          classifications = keywords['thresholds'].get(exposure_key)
      else:
          classifications = keywords['value_maps'].get(exposure_key)
      if classifications is None:
          return None
      for value in list(classifications.values()):
          if value['active']:
              return value['classes']
      return None
docs: Helper to retrieve active value maps or thresholds for an exposure.
  
      :param keywords: Hazard layer keywords.
      :type keywords: dict
  
      :param exposure_key: The exposure key.
      :type exposure_key: str
  
      :returns: Active thresholds or value maps.
      :rtype: dict