fix: close file

[m9810223]

A fix to close files after writing.

[lukebakken]

Hello, thanks for your contribution. How did you determine that this change should be made?

[m9810223]

Hi @lukebakken!

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In Python, file object has a close method.

To call the method, add () after the method, like xxx.close().

If you don't want to close the file, Python will close it when the program exits
And we don't need the line xxx.close.

https://docs.python.org/3/tutorial/inputoutput.html#reading-and-writing-files

[lukebakken]

Thank you. I would have expected the current code to warn us that .close is not a real member, but, that's Python for you 🙄