maint: modifying files to conform with "PTH" ruff rule #6647

Job	Run time
pick_server_suffix	1s
debug	1s
Build linux1 wheel	17s
retro 222	0s
retro 231	0s
retro 232	0s
retro 241	0s
retro 242	0s
retro 251	0s
Style Check	50s
docs	0s
examples	0s
PyDPF-Post	0s
Build and Test on Docker / Build and Test On Docker (3.9, ubuntu-latest)	26m 31s
tests / Setup	1s
Run examples on Docker / Setup	1s
tests_any / Setup	1s
upload-development-docs	0s
tests_any / Tests (3.9, windows-latest)	22m 23s
tests_any / Tests (3.9, ubuntu-latest)	18m 35s
tests / Tests (3.9, windows-latest)	22m 1s
tests / Tests (3.9, ubuntu-latest)	16m 36s
Run examples on Docker / Run Examples (3.9, ubuntu-latest)	22m 48s
	2h 10m 6s

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