code: def _round(self, multiple=1):
          
          for pair, value in self.items():
              value = int(normalizers.normalizeRounding(
                  value / float(multiple))) * multiple
              self[pair] = value
docs: This is the environment implementation of
          :meth:`BaseKerning.round`. **multiple** will be an ``int``.
  
          Subclasses may override this method.