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Subject: Re: How to improve the usability of nested packages
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From: "Stefan H. Holek" <stefan@epy.co.at>
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Date: Fri, 2 Nov 2012 19:23:00 +0100
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Hi Michael,

What we have learned from creating the Zope Toolkit (formerly Zope 3), =
is that __init__.py files in namespace packages should be empty, and =
imports should be absolute. [1]

That said, there are ways to avoid import cycles. One is to very =
carefully craft your modules so they do not have to import from each =
other. Another is to not have imports at the module level, but move them =
into the functions where they are required. Third, large libraries like =
the Zope Toolkit usually have mechanisms to defer imports to some point =
after initial loading. You may want explore this direction as well. [2]

(Not trying to plug the ZTK here, it just happens to be a large, =
namespace-using library I know.)

Hope this helps,
Stefan

[1] http://docs.zope.org/zopetoolkit/
[2] http://pypi.python.org/pypi/zope.deferredimport

--=20
Stefan H. Holek
stefan@epy.co.at