in python-docx, I try to read the font size, but I get None - python-docx

Question

My task is to check several docx documents for font properties, like font name, size, boldness, italic etc. I do not want to change anything, just validate if there are correct values.
I created a small test document, with text "Foo-bar" and I have updated the font name to Garamond from the default, but have not changed the font size.
Now I am able to read the font name from the document, but when I try to read the font size, I get None.
from docx import Document
from docx.enum.text import WD_ALIGN_PARAGRAPH
def check_para_props(doc, paralist, ffamily, fsize, paligin):
pargs = doc.paragraphs
for i in paralist:
para = pargs[i]
print(i, para.text)
for run in para.runs:
print(run.font.name, run.font.size)
worddoc = Document('Foo-bar.docx')
# pass the document, the paragraphs list which should be tested
# and the expected values
check_para_props(worddoc, (0, ), 'Garamond', 11, WD_ALIGN_PARAGRAPH.JUSTIFY)
Output:
0 Foo-bar
Garamond **None**
I assume, there is some default values in docx for the unchanged values, like font-size, but have not found, how could I read them from the document. In python-docx documentation I have not found an API call for it: https://python-docx.readthedocs.io/en/latest/index.html
I have checked the style section, which is readable, but I don't think, this is set there.
Checked API documentation: https://python-docx.readthedocs.io/en/latest/index.html
Word is able to export document in XML format, but still I have doubts how to read the font size.
In that article, I read the about the inheritance of the properties: https://www.toptal.com/xml/an-informal-introduction-to-docx
It tells, to get the end result of a character’s properties you should:
Use default run/paragraph properties
Append run/paragraph style properties
Append local run/paragraph properties
Append result run properties over paragraph properties
Ok, still how may I read the default properties using python-docx?
Please advise!
Thank you in advance!