cdblib.py obviously owes a debt to D. J. Bernstein (http://cr.yp.to/djb.html)
for the cdb specification (http://cr.yp.to/cdb.html) and the original C
implementation for Unix.

cdblib.py is a from-scratch Python implementation by John E. Barham
(jbarham@jbarham.com), with an optional C extension module that includes an
implementation of the cdb hash function and a memory efficient index for cdb
hash tables.