Setting the footer text to a string that starts with a number and contains a non-numeric character prevents proper setting of the footer text size.

Created originally on Bitbucket by Kendallsearing (Kendall Searing)

The below code creates a footer with a left section font size of 409.

#!python

#!/usr/bin/env python
# -*- coding: utf-8 -*- 

import openpyxl
import os

root = os.path.dirname(os.path.abspath(__file__))
file = root + "/footer test.xlsx"

book = openpyxl.Workbook()
sheet = book.active
sheet.sheet_view.view = "pageLayout"

sheet.oddFooter.left.text = "2017s"
sheet.oddFooter.left.size = 8
	
book.save(file)

Attachments: sheet1.xml