How do you insert a lxml tag with namespace while skipping xmlns?

Question

I'm trying to write my python scripts using python-docx to add equations to docx files. Since this is not supported by python-docx yet, I need to modify the OOXML directly using lxml. I'd need to add some tags so the resulting XML looks like this:

<m:r>
    <m:t>(5−x)</m:t>
</m:r>

I can't create a new naked <m:r> node using lxml. Using something like the following code

new_node = etree.Element('{m}r', nsmap={'m': ''})

gives me a <m:r xmlns:m="m"> node, except I don't need the xmlns part. (python-docx handles the remaining XML operations for me, and if the xmlns is there, the docx file actually wouldn't be recognised by MS Word.) Is there any way to make a naked <m:r> node?

Answer 1

python-docx is aware of the "m": "http://schemas.openxmlformats.org/officeDocument/2006/math" namespace-prefix mapping: https://github.com/python-openxml/python-docx/blob/master/docx/oxml/ns.py#L18

So you can use python-docx internals to create such an element:

from docx.oxml import OxmlElement

r = OxmlElement("m:r")

You can then use that element like you would any other lxml element, like appending or inserting it as a child of some other element.