Raise KeyError: /Parent when attempting to extract the text from an empty page using layout mode

[amznero]

pypdf will raise a KeyError: /Parent when attempting to extract the text from an empty page using layout mode. (Default mode works fine)

Environment

ubuntu 22.04 + py3.10 + pypdf4.1.0

$ python test.py

Code + PDF

from pypdf import PdfReader
reader = PdfReader("test.pdf")
pages = reader.pages
for page in pages:
    text = page.extract_text()# works fine!
    text = page.extract_text(extraction_mode="layout")# raise KeyError

Share here the PDF file(s) that cause the issue. The smaller they are, the
better. Let us know if we may add them to our tests!

Traceback

This is the complete traceback I see:

Traceback (most recent call last):
  File "/mnt/d/codes/tmp/test.py", line 6, in <module>
    text = page.extract_text(extraction_mode="layout")# raise KeyError
  File "/home/hello/.local/lib/python3.10/site-packages/pypdf/_page.py", line 2050, in extract_text
    return self._layout_mode_text(
  File "/home/hello/.local/lib/python3.10/site-packages/pypdf/_page.py", line 1948, in _layout_mode_text
    fonts = self._layout_mode_fonts()
  File "/home/hello/.local/lib/python3.10/site-packages/pypdf/_page.py", line 1895, in _layout_mode_fonts
    objr = objr["/Parent"].get_object()


  File "/home/hello/.local/lib/python3.10/site-packages/pypdf/generic/_data_structures.py", line 319, in __getitem__
    return dict.__getitem__(self, key).get_object()
KeyError: '/Parent'

test.pdf

[stefan6419846]

Thanks for the report. Do you want to submit a corresponding PR?