## A.3.1 Mersenne Twister

The `_random` module includes code based on a download from http://www.math.keio.ac.jp/~matumoto/MT2002/emt19937ar.html. The following are the verbatim comments from the original code:

    A C-program for MT19937, with initialization improved 2002/1/26.
    Coded by Takuji Nishimura and Makoto Matsumoto.

    Before using, initialize the state by using init_genrand(seed)
    or init_by_array(init_key, key_length).

    Copyright (C) 1997 - 2002, Makoto Matsumoto and Takuji Nishimura,
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