Exceptions when working with own document

[me21]

I saved an empty docx file in my Microsoft Word. When I open it with python-docx and try to add a heading, I get KeyError: "no style with name 'Heading 1'". My code looks like document.add_heading('Visitor Information', level=1).

If I open that empty document, add a heading of the 1st level, then delete it again, and save the document, the code works.

[scanny]

Yep, definitely. Try listing out the style names and picking one of those, something like:

for style in document.styles:
    print(style.name)

You might want to narrow it down to paragraph styles. You can also probably use the name the way it shows up in the version of Word you used to create the document if that's faster.

[me21]

Is it possible to add a style programmatically?

[me21]

Your code snippet returned:

Normal
Default Paragraph Font
Normal Table
No List

If I add document.styles.add_style('Heading 1', docx.enum.style.WD_STYLE_TYPE.PARAGRAPH, builtin=True), the error is gone.

But another similar error remains when I use list_number from haggis package to add a numbered list to the Word document. The error thrown is

  File "C:\Users\azarubkin\Documents\Python Projects\edoc2\venv\Lib\site-packages\haggis\files\docx.py", line 578, in list_number
    numbering = doc.part.numbering_part.numbering_definitions._numbering
                ^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\azarubkin\Documents\Python Projects\edoc2\venv\Lib\site-packages\docx\shared.py", line 242, in __get__
    value = self._fget(obj)
            ^^^^^^^^^^^^^^^
  File "C:\Users\azarubkin\Documents\Python Projects\edoc2\venv\Lib\site-packages\docx\parts\document.py", line 99, in numbering_part
    numbering_part = NumberingPart.new()
                     ^^^^^^^^^^^^^^^^^^^
  File "C:\Users\azarubkin\Documents\Python Projects\edoc2\venv\Lib\site-packages\docx\parts\numbering.py", line 15, in new
    raise NotImplementedError