code: def truncate(self, size):
      
      if size > len(self):
        raise NGSReadError("Trying to truncate NGS read to size " + str(size) +
                           ", but read is only " + str(len(self)) +
                           " nucleotides long")
      if size < 0:
        raise NGSReadError("Trying to truncate NGS read to size less than 0")
  
      self.trimRight(len(self) - size)
docs: truncate this fastqSequence in-place so it is only <size> nucleotides
        long
  
        :param size: the number of nucleotides to truncate to.