docs: def random_kmer(self):
          """
          m.random_kmer() -- Generate one of the many k-mers that matches the motif.  See m.emit() for a more probabilistic generator
          
          """
          if not self._bestseqs: self._bestseqs = self.bestseqs()
          seqs   = self._bestseqs
          pos = int(random() * len(seqs))
          print 'Random: ',self.oneletter,seqs[pos][1]
          return(seqs[pos][1])