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From: Robert Kern <robert.kern@gmail.com>
Subject: Re: Pure Python Data Mangling or Encrypting
Date: Sat, 27 Jun 2015 09:07:21 +0100
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On 2015-06-27 08:58, Robert Kern wrote:
> On 2015-06-27 04:38, Steven D'Aprano wrote:
>
>> Maybe you use Python's standard library and the Mersenne Twister. The period
>> of that is huge, possibly bigger than 256! (or not, I forget, and I'm too
>> lazy to look it up). So you think that's safe. But it's not: Mersenne
>> Twister is not a cryptographically secure pseudorandom number generator. If
>> I can get some small number of values from the Twister (by memory,
>> something of the order of 100 such values) then I can predict the rest for
>> ever.
>
> 634.

Bah! 624.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco