The current working directory (CWD) of the debugger session starts in the NetBeans install directory. This is fine
except if scripts are expecting the CWD to be the directory where the script is located. That is the normal case from
the shell, and also if you run the project from NetBeans without the debugger (e.g. with the F6 key).

Because the CWD is the NetBeans install directory, any python file operations for files expected to be in the same
directory as the script file will fail with "No such file or directory: ..." errors when run in the debugger, but will
work fine normally.

A work-around:

Set a break-point before opening any files etc. Start the debugger, run to the break-point, then issue this from the
interactive Debugging window:

>>> import os
>>> os.chdir('<path_to_project>/src')

You can then continue debugging with the runtime in the expected state.

Suggest the CWD should be the debugging project's /src directory, since this is what it is when you run the project
normally.