python - How to get product without repeating elements

Question

For example, for code like this

from itertools import product
lst = [[1,2], [2,3], [4,5,6]]
for i in product(*lst):
    print(i)

I get

(1, 2, 4)
(1, 2, 5)
(1, 2, 6)
(1, 3, 4)
(1, 3, 5)
(1, 3, 6)
(2, 2, 4)
(2, 2, 5)
(2, 2, 6)
(2, 3, 4)
(2, 3, 5)
(2, 3, 6)

but I would like to get

(1, 2, 4)
(1, 2, 5)
(1, 2, 6)
(1, 3, 4)
(1, 3, 5)
(1, 3, 6)  
(2, 3, 4)
(2, 3, 5)
(2, 3, 6)

Tell me how this can be done using itertools.

question from:https://stackoverflow.com/questions/65651485/how-to-get-product-without-repeating-elements

Answer 1

You can add a filter step that checks that there is 3 different values in the tuple

lst = [[1, 2], [2, 3], [4, 5, 6]]
for i in filter(lambda x: len(set(x)) == 3, product(*lst)):
    print(i)

Of course, the use of an if is also possible, performance is about the same

for i in product(*lst):
     if len(set(i)) == 3:
         print(i)