Error with module 'fu_stdout' when running from Resolve on MacOS

[mivk]

On MacOS (15.7.1), the script works when started from Terminal. But when started from Resolve (20.2.1), it aborts after clicking "Export stills" and the console shows:

Unable to find module DaVinciResolveScript from $PYTHONPATH - trying default locations
Unable to find module DaVinciResolveScript - please ensure that the module DaVinciResolveScript is discoverable by python
For a default DaVinci Resolve installation, the module is expected to be located in: /Library/Application Support/Blackmagic Design/DaVinci Resolve/Developer/Scripting/Modules/
Exception ignored on flushing sys.stdout:
Traceback (most recent call last):
  File "/Users/andromeda/Library/Application Support/Blackmagic Design/DaVinci Resolve/Fusion/Scripts/Utility/Marks2Pics/NJUPIXEL_DAVINCI_RESOLVE_MARKERS_TO_IMAGES.py", line 377, in <module>
    app.exec()
AttributeError: module 'fu_stdout' has no attribute 'flush'
Exception ignored in sys.unraisablehook: <built-in function unraisablehook>
AttributeError: module 'fu_stderr' has no attribute 'flush'

The DaVinciResolveScript module is in the "expected" location, and PYTHONPATH is defined in ~/.bash_profile:

$ echo $PYTHONPATH
/Library/Application Support/Blackmagic Design/DaVinci Resolve/Developer/Scripting/Modules/

However, it does not show up in the Resolve console environment (using import sys and print(os.environ)).

But anyway, the main problem seems to be the second part, which the console shows in red:

Exception ignored on flushing sys.stdout:
Traceback (most recent call last):
  File "/Users/andromeda/Library/Application Support/Blackmagic Design/DaVinci Resolve/Fusion/Scripts/Utility/Marks2Pics/NJUPIXEL_DAVINCI_RESOLVE_MARKERS_TO_IMAGES.py", line 377, in <module>
    app.exec()
AttributeError: module 'fu_stdout' has no attribute 'flush'
Exception ignored in sys.unraisablehook: <built-in function unraisablehook>
AttributeError: module 'fu_stderr' has no attribute 'flush'

In case it is relevant, Python is version 3.13.8, installed with Homebrew.