Сочетание элементов

from itertools import combinations
from math import comb
 
a = {1, 2, 3, 4, 5}
k = 3
for p in combinations(a, 3):
    print(*p, sep='')
print('Кол-во сочетаний:', comb(len(a), k))

def combinations_with_replacement(iterable, r):
    # combinations_with_replacement('ABC', 2) --> AA AB AC BB BC CC
    pool = tuple(iterable)
    n = len(pool)
    if not n and r:
        return
    indices = [0] * r
    yield tuple(pool[i] for i in indices)
    while True:
        for i in reversed(range(r)):
            if indices[i] != n - 1:
                break
        else:
            return
        indices[i:] = [indices[i] + 1] * (r - i)
        yield tuple(pool[i] for i in indices)
 
 
def combinations_without_replacement(iterable, r):
    # combinations('ABCD', 2) --> AB AC AD BC BD CD
    # combinations(range(4), 3) --> 012 013 023 123
    pool = tuple(iterable)
    n = len(pool)
    if r > n:
        return
    indices = list(range(r))
    yield tuple(pool[i] for i in indices)
    while True:
        for i in reversed(range(r)):
            if indices[i] != i + n - r:
                break
        else:
            return
        indices[i] += 1
        for j in range(i + 1, r):
            indices[j] = indices[j - 1] + 1
        yield tuple(pool[i] for i in indices)
 
 
a = {1, 2, 3, 4, 5}
k = 3
match input('С повторениями? ').lower():
    case 'да':
        combs = list(combinations_with_replacement(a, k))
    case _:
        combs = list(combinations_without_replacement(a, k))
 
for p in combs:
    print(*p, sep='')
print('Кол-во сочетаний:', len(combs))