# combopermute.py

# combopermute.py

def combinations(iterable, r):
    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)

def all_perms(elements):
    if len(elements) <=1:
        yield elements
    else:
        for perm in all_perms(elements[1:]):
            for i in range(len(elements)):
                yield perm[:i] + elements[0:1] + perm[i:]

def combopermute(l, n):
    for i in combinations(l, n):
        for j in all_perms(i):
            yield j

# speed demonstration
l = [1,2,3,9]
n = 3
test = combopermute(l, n)

for t in test:
    print(t)

(1, 2, 3)
(2, 1, 3)
(2, 3, 1)
(1, 3, 2)
(3, 1, 2)
(3, 2, 1)
(1, 2, 9)
(2, 1, 9)
(2, 9, 1)
(1, 9, 2)
(9, 1, 2)
(9, 2, 1)
(1, 3, 9)
(3, 1, 9)
(3, 9, 1)
(1, 9, 3)
(9, 1, 3)
(9, 3, 1)
(2, 3, 9)
(3, 2, 9)
(3, 9, 2)
(2, 9, 3)
(9, 2, 3)
(9, 3, 2)