KnowCardPython · Files & I/O
Predict: you open a file with mode "a" and call f.seek(0) then f.write("X"). Where does "X" land?
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More in Files & I/O
Why prefer with open(...) as f: over a manual open() / f.close() pair?
What does open("out.txt", "w") do to an existing file before you write anything?
Name the core single-letter file modes for open() and what each does when the file already exists.
You open with "r" and the file does not exist. What happens — and how does that differ from "w"?
Difference between text mode ("t", default) and binary mode ("b") — what type comes back from read()?
Why can specifying encoding= matter, and what does Python use if you omit it in text mode?
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