code: def scan(self, seqs, nreport=100, scan_rc=True, normalize=False):
          
  
          if not self.threshold:
              sys.stderr.write(
                  "Using default threshold of 0.95. "
                  "This is likely not optimal!\n"
                  )
              self.set_threshold(threshold=0.95)
  
          seqs = as_fasta(seqs, genome=self.genome)
             
          it = self._scan_sequences(seqs.seqs, 
                      nreport, scan_rc)
         
          if normalize:
              if len(self.meanstd) == 0:
                  self.set_meanstd()
              mean_std = [self.meanstd.get(m_id) for m_id in self.motif_ids]
              means = [x[0] for x in  mean_std]
              stds = [x[1] for x in  mean_std]
  
  
          for result in it:
              if normalize:
                  zresult = [] 
                  for i,mrow in enumerate(result):
                      mrow = [((x[0] - means[i]) / stds[i], x[1], x[2]) for x in mrow]
                      zresult.append(mrow)
                  yield zresult
              else:
                  yield result
docs: scan a set of regions / sequences