code: def map_legend_attributes(self):
          
          LOGGER.debug('InaSAFE Map getMapLegendAttributes called')
          legend_attribute_list = [
              'legend_notes',
              'legend_units',
              'legend_title']
          legend_attribute_dict = {}
          for legend_attribute in legend_attribute_list:
              # noinspection PyBroadException
              try:
                  legend_attribute_dict[legend_attribute] = \
                      self._keyword_io.read_keywords(
                          self.impact, legend_attribute)
              except KeywordNotFoundError:
                  pass
              except Exception:  # pylint: disable=broad-except
                  pass
          return legend_attribute_dict
docs: Get the map legend attribute from the layer keywords if possible.
  
          :returns: None on error, otherwise the attributes (notes and units).
          :rtype: None, str