All permutations from 2 lists

[Cameron Simpson]

On 02Mar2022 08:29, Larry Martell <larry.martell at gmail.com> wrote:
>On Tue, Mar 1, 2022 at 7:32 PM Rob Cliffe <rob.cliffe at btinternet.com> wrote:
>> I think itertools.product is what you need.
>> Example program:
>>
>> import itertools
>> opsys = ["Linux","Windows"]
>> region = ["us-east-1", "us-east-2"]
>> print(list(itertools.product(opsys, region)))
>
>This does not work if region = []. I wrote in question that either
>list could be empty.

What do you want to get if a list is empty? You haven't said. My 
personal expectation would be an empty result.

Alternatively, if you expect an empty list to imply some single default 
the the experession:

    the_list or (the_default,)

might be of use.

Cheers,
Cameron Simpson <cs at cskk.id.au>