code: def FastaIter(handle):
      
  
      header = None
      for line in handle:
          if line.startswith(">"):
              if header is not None:  # not the first record
                  yield header, "".join(seq_lines)
              seq_lines = list()
              header = line[1:].rstrip()
          else:
              if header is not None:  # not the first record
                  seq_lines.append(line.strip())
  
      if header is not None:
          yield header, "".join(seq_lines)
      else:   # no FASTA records in file
          return
docs: generator that returns (header, sequence) tuples from an open FASTA file handle
  
      Lines before the start of the first record are ignored.