code: def get_calendar_class(self, iso_code):
          
          code_elements, is_subregion = self._code_elements(iso_code)
          if is_subregion and iso_code not in self.region_registry:
              # subregion code not in region_registry
              code = code_elements[0]
          else:
              # subregion code in region_registry or is not a subregion
              code = iso_code
          return self.region_registry.get(code)
docs: Retrieves calendar class associated with given ``iso_code``.
  
          If calendar of subdivision is not registered
          (for subdivision like ISO codes, e.g. GB-ENG)
          returns calendar of containing region
          (e.g. United Kingdom for ISO code GB) if it's available.
  
          :rtype: Calendar