docs: def percentNuc(self, nuc):
      """
        return the percentage of the sequence which is equal to the passed nuc.
  
        :param nuc: the nucleotide to compute percentage composition for. There
                    is no check to make sure this is a valid nucleotide.
        :return: the percentage of the sequence that is <nuc>
      """
      count = reduce(lambda x, y: x + 1 if y == nuc else x, self.sequenceData, 0)
      return count / float(len(self.sequenceData))