[Biopython] IUPAC code contribution

[Michal]

Hello,
I would like to contribute the following IUPAC function to Biopython:

def iupac_base(alignment):
     IUPAC = {
       ord('N'): 'N',
       ord('G'): 'G',
       ord('A'): 'A',
       ord('T'): 'T',
       ord('C'): 'C',
       ord('G') + ord('A'): 'R',
       ord('T') + ord('C'): 'Y',
       ord('A') + ord('C'): 'M',
       ord('G') + ord('T'): 'K',
       ord('G') + ord('C'): 'S',
       ord('A') + ord('T'): 'W',
       ord('A') + ord('C') + ord('T'): 'H',
       ord('G') + ord('T') + ord('C'): 'B',
       ord('G') + ord('C') + ord('A'): 'V',
       ord('G') + ord('A') + ord('T'): 'D',
       ord('G') + ord('A') + ord('T') + ord('C'): 'N'}

     return IUPAC[sum(map(ord, {}.fromkeys(alignment).keys()))]


a = iupac_base(['A','A','T','T','T'])

Cheers,
Michal