code: def summary(self, sortOn=None):
          
          titles = self if sortOn is None else self.sortTitles(sortOn)
  
          for title in titles:
              yield self[title].summary()
docs: Summarize all the alignments for this title.
  
          @param sortOn: A C{str} attribute to sort titles on. One of 'length',
              'maxScore', 'medianScore', 'readCount', or 'title'.
          @raise ValueError: If an unknown C{sortOn} value is given.
          @return: A generator that yields C{dict} instances as produced by
              C{TitleAlignments} (see class earlier in this file), sorted by
              C{sortOn}.