convert list of lists to list

[Fredrik Lundh]

Fredrik Lundh wrote:

>> ['klas* * *', 'mooi* * * *, 'koe',  'arm* * * (haar)',  'groei* * * *
>> *']
> 
> if there's only one level of recursion, and the lists aren't too long, 
> you can simply do:
> 
>     sum(list_of_lists, [])

oops.  that's what you get for taking the subject line too literally...