# 1. Print all combinations
from itertools import combinations
comb = combinations([1, 1, 3], 2)
print(list(combinations([1, 2, 3], 2)))
# Output: [(1, 2), (1, 3), (2, 3)]
# 2. Counting combinations
from math import comb
print(comb(10,3))
#Output: 120
itertools.combinations(iterable, r)all_combinations = [list(zip(each_permutation, list2)) for each_permutation in itertools.permutations(list1, len(list2))]import math
n=7
k=5
print(math.comb(n, k))import itertools
def subs(l):
res = []
for i in range(1, len(l) + 1):
for combo in itertools.combinations(l, i):
res.append(list(combo))
return res
def combinations(iterable, r):
pool = tuple(iterable)
n = len(pool)
for indices in permutations(range(n), r):
if sorted(indices) == list(indices):
yield tuple(pool[i] for i in indices)