Error from xlsm file when adding strings to a xltm template

Created originally on Bitbucket by egene (Elizabeth Gene)

This sample code:

#!python

from openpyxl import load_workbook
wb = load_workbook('template.xltm', keep_vba=True) 
ws = wb.active 
cell = ws.cell(column=1, row=1, value='42')
wb.save('sample_book.xlsm') 

produces a corrupted spreadsheet when run on Ubuntu with these versions:

• Python 2.7.6
• lxml Version: 3.5.0
• openpyxl Version: 2.3.3

If the value is changed to an int, the spreadsheet is fine.

Attachments: sample_book.xlsmtemplate.xltmBildschirmfoto_2016-01-29_um_17.05.42