Hello, ZPUGDC

We have a Page Template with a single line of code <div 
tal:replace="structure python:here.externalmethod"/> that is replaced 
with well-formed XML data.

If the Page Template 'content_type' is not set to 'text/xml', then XML 
parsers will not recognize the page as a legitimate XML document. Since 
the default Page Template 'content_type' metadata is 'text/html' we must 
change it to 'text/xml'.

Bizarely, this content_type change works until someone uses the ZMI.

Then the Zope parser tests the Page Template and throws an XML parser 
error because the HTML/TAL code isn't what it expects. It isn't smart 
enough to realize that the TAL code is being replaced with XML upon 
execution.

What the heck should we do to prevent Zope from test XML parsing the 
Page Template?
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