get_combinations.py

from itertools import product, compress


def combinations(items):
   return (set(compress(items,mask)) for mask in product(*[[0,1]]*len(items)))
  
vals = [1, 2, 3, 4, 5, 6, 7, 8, 9]
combs = combinations(vals)
count = 0
for comb in combs:
  count += 1

print(count)