code: def codonInformation(codons1, codons2):
      
      result = defaultdict(list)
      for c1 in codons1:
          for c2 in codons2:
              distance = findDistance(c1, c2)
              result[distance].append([c1, c2])
  
      return result
docs: Take two C{list} of codons, and returns information about the min and
      max distance between them.
  
      @param codon1: a C{list} of codons.
      @param codon2: a C{list} of codons.
  
      @return: a dict whose keys are C{int} distances and whose values are lists
          of pairs of codons.