If you work with strings in your Python scripts and you're writing obscure logic to process them, then you need to look into ...
[DEFAULT] img_file = /dir/to/SKA/SDC3/ZW3.msw_image.fits test_img_file = /dir/to/SKA/SDC3/TestDataset.msw_image.fits beam_file = /dir/to/SKA/SDC3/station_beam.fits ...