Python for Absolute Beginners Transcripts
Chapter: Course conclusion
Lecture: Review: File I/O
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Once we rewrote our Rock Paper Scissor game
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with data structures
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it turns out it's pretty easy
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to save and load those data structures from files.
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The next topic we covered was File IO
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and File IO usually starts around the open function.
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The open function creates this file string
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either an input or output string
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and you need to make sure
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it gets flushed and closed properly
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so you want to put it into a width block.
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That's what we're doing at the bottom
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of this screen here.
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With open, give it a file, this one's for reading
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so we say R, specify the encoding just to be explicit there
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and we give it a variable name, Fin.
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I like fin for file input string
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so the name tells you, you can't write to it
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and here we're actually going to load up a JSON file
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so we don't need to understand how JSON works.
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All we need to do is input the JSON library
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and say, hey, here's a file string
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to something you understand.
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Go get us the data, put it into rows.
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That will be a dictionary on the Python side of things.
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We also saw that working with paths is tricky
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and knowing where you're actually located
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can be a challenge.
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Remember, this is based on the working directory.
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And trying to put these together and work with them
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is also tricky in a cross-platform way.
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Windows and POSIX macOS, Linux systems
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have different separators and definitions
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of how you put files together.
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That's why we use the OS.path module
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because it knows how to do this for us
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regardless of the operating system we're on.
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This is just one of the things
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we did with files throughout the course
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and I think you'll agree
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they added a lot to our little program.
