Edit word (.docx) file using Python when it is opened in Word

Question

I write python script to edit MS Office Word documents. It is very important for me to edit .docx file when it is opened in Word. Python must change it. I use python library docx to do it. Code works fine, but it cannot edit ms-word document when it is opened in MS Word. I get error

PermissionError: [Errno 13] Permission denied: 'demo.docx'

To solve this problem I tried everything recommended in this post:

PermissionError: [Errno 13] Permission denied

1. Running cmd.exe as and admin
2. Creating shortcut with elevated privileges
3. Changing the permissions on the python executable

Nothing helps. I always get Error:

PermissionError: [Errno 13] Permission denied: 'demo.docx'

Python code doesn't matter, but I post it here too (code works, problem is in permissions):

from docx import Document
from docx.shared import Inches
import traceback 
try: 
    document = Document()
    document.add_heading('Document Title', 0)
    p = document.add_paragraph('A plain paragraph having some ')
    p.add_run('bold').bold = True
    p.add_run(' and some ')
    p.add_run('italic.').italic = True
    document.add_heading('Heading, level 1', level=1)
    document.add_paragraph('Intense quote', style='Intense Quote')
    document.add_paragraph(
        'first item in unordered list', style='List Bullet'
    )
    document.add_paragraph(
        'first item in ordered list', style='List Number'
    )
    #document.add_picture('monty-truth.png', width=Inches(1.25))
    records = (
        (3, '101', 'Spam'),
        (7, '422', 'Eggs'),
        (4, '631', 'Spam, spam, eggs, and spam')
    )
    table = document.add_table(rows=1, cols=3)
    hdr_cells = table.rows[0].cells
    hdr_cells[0].text = 'Qty'
    hdr_cells[1].text = 'Id'
    hdr_cells[2].text = 'Desc'
    for qty, id, desc in records:
        row_cells = table.add_row().cells
        row_cells[0].text = str(qty)
        row_cells[1].text = id
        row_cells[2].text = desc
    document.add_page_break()
    document.save('demo.docx')
except:
    traceback.print_exc() 

Answer 1

As mentioned in the comments, you cannot modify a Word document that is already open with another application (namely: python-docx module).

However, you can access directly Word (same thing with Excel) by using win32api / pywin32.

You can do everything you could do with VBA with a syntax that is similar (just translated to Python).

It's heavy and ugly, but at least it works.

This is an example of code from this blog: https://www.blog.pythonlibrary.org/2010/07/16/python-and-microsoft-office-using-pywin32/

import win32com.client as win32

RANGE = range(3, 8)

def edit_word():
    word = win32.gencache.EnsureDispatch('Word.Application')
    doc = word.Documents.Add()
    word.Visible = True
    rng = doc.Range(0,0)
    rng.InsertAfter('Hacking Word with Python\r\n\r\n')
    sleep(1)
    for i in RANGE:
        rng.InsertAfter('Line %d\r\n' % i)
        sleep(1)
    rng.InsertAfter("\r\nPython rules!\r\n")
    doc.Close(False)
    word.Application.Quit()