All permutations from 2 lists

[Antoon Pardon]

Op 2/03/2022 om 14:27 schreef Larry Martell:
> On Tue, Mar 1, 2022 at 7:21 PM<2QdxY4RzWzUUiLuE at potatochowder.com>  wrote:
>> On 2022-03-01 at 19:12:10 -0500,
>> Larry Martell<larry.martell at gmail.com>  wrote:
>>
>>> If I have 2 lists, e.g.:
>>>
>>> os = ["Linux","Windows"]
>>> region = ["us-east-1", "us-east-2"]
>>>
>>> How can I get a list of tuples with all possible permutations?
>>>
>>> So for this example I'd want:
>>>
>>> [("Linux", "us-east-1"), ("Linux", "us-east-2"), ("Windows",
>>> "us-east-1"), "Windows", "us-east-2')]
>>>
>>> The lists can be different lengths or can be 0 length. Tried a few
>>> different things with itertools but have not got just what I need.
>> [(o, r) for o in os for r in region]
> This does not work if region = []. I wrote in my question that either
> list could be empty.

What do you mean it doesn't work? The result seems to be an empty list,
which IMO is a perfectly valid result.

All possible permutations over two collections where one collection is
empty, should IMO give you an empty collection.

-- 
Antoon Pardon.