code: def get_sequences(self, chr, coords):
              
          # Check if we have an index_dir
          if not self.index_dir:
              print("Index dir is not defined!")
              sys.exit()
  
          # retrieve all information for this specific sequence
          fasta_file = self.fasta_file[chr]
          index_file = self.index_file[chr]
          line_size = self.line_size[chr]
          total_size = self.size[chr]
          index = open(index_file, "rb")
          fasta = open(fasta_file)
          
          seqs = []
          for coordset in coords:
              seq = ""
              for (start,end) in coordset: 
                  if start > total_size:
                      raise ValueError("%s: %s, invalid start, greater than sequence length!" % (chr,start))
              
                  if start < 0:
                      raise ValueError("Invalid start, < 0!")
                  
                  if end > total_size:
                      raise ValueError("Invalid end, greater than sequence length!")
  
  
                  seq += self._read(index, fasta, start, end, line_size)
              seqs.append(seq)
          index.close()
          fasta.close()
  
          return seqs
docs: Retrieve multiple sequences from same chr (RC not possible yet)