how to make a nested list

[Prasad, Ramit]

>>> B = 3 * [ [ None, None ]]
That makes a list of the exact same list object: [ a, a, a ] where a = [ None, None ]. 
Instead I would do something like (untested python2.x):
B = [ [ None, None ] for x in xrange(3) ]

Ramit


Ramit Prasad | JPMorgan Chase Investment Bank | Currencies Technology
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