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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Wed, 8 Oct 2014 16:44:04 -0600
Subject: Re: how to add custom importer after the normal imports
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Xref: csiph.com comp.lang.python:78860

On Wed, Oct 8, 2014 at 4:53 AM, Gelonida N <gelonida@gmail.com> wrote:
> Hi,
>
>
> I just read about sys.meta_path, which allows to install custom importers
> *BEFORE* the default importers.
>
> However I have a use case where I would like to add a custom importer
> *AFTER* all other import methods have failed.
>
> Does anybody know how to do this.
>
> One way of implementing this would be to add the default importer as first
> entry in sys.meta_path. My only problem is, that I don't know how to create
> a 'default-importer', such that I can add it into sys.meta_path

As of CPython 3.3 the default importers are already in sys.meta_path,
so you could just add your custom importer to the end. If you need to
support earlier versions or alternate implementations then this may
not be reliable.