Python etree control empty tag format

Question

When creating an XML file with Python\'s etree, if we write to the file an empty tag using SubElement, I get:

Answer 1

As of Python 3.4, you can use the short_empty_elements argument for both the tostring() function and the ElementTRee.write() method:

>>> from xml.etree import ElementTree as ET
>>> ET.tostring(ET.fromstring(''), short_empty_elements=False)
b''

In older Python versions, (2.7 through to 3.3), as a work-around you can use the html method to write out the document:

>>> from xml.etree import ElementTree as ET
>>> ET.tostring(ET.fromstring(''), method='html')
''

Both the ElementTree.write() method and the tostring() function support the method keyword argument.

On even earlier versions of Python (2.6 and before) you can install the external ElementTree library; version 1.3 supports that keyword.

Yes, it sounds a little weird, but the html output mostly outputs empty elements as a start and end tag. Some elements still end up as empty tag elements; specifically , ,
and such. Still, it's that or upgrade your Fortran XML parser to actually parse standards-compliant XML!