A comment to the paragraph below was recently added via http://www.zope.org/Documentation/Books/ZopeBook/current/CustomZopeObjects.stx#2-38
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"Example Class Inheritance":img:12-3:Figures/12-3.png
% Anonymous User - Sep. 18, 2002 11:33 am:
Technically a Frog is-a amphibian rather than a reptile.