idiom for initial list of lists

[Robin Becker]

In article <slrn8rqkv0.2p7.hzhu at rocket.knowledgetrack.com>, Huaiyu Zhu
<hzhu at users.sourceforge.net> writes
>Here's the timing results and program for various methods suggested here.
>The winner (on my machine) is list_list.  It is suprising that list_tuple
>did worse, and that copy_list is the worst.

copy.copy is two levels of function call copy._copy_list would be only
one level till you get to x[:]

...
-- 
Robin Becker