Using itertools to count the number of possible genotypes given a certain ploidy

ploidy.py

#!/usr/bin/env python
from itertools import *




#print the number of possible genotypes with various ploidies
ploidys=[2,3,4,5,6,7,8,9,10]
for p in ploidys:
    print p, len([combo  for combo in combinations_with_replacement(['A','C','G','T'],p) ])

#output
#2 10
#3 20
#4 35
#5 56
#6 84
#7 120
#8 165
#9 220
#10 286