Python: BufferedRWPair Undefined Behavior #3884
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The BufferedRWPair class in the io module does not synchronize accesses to its streams. As noted in the official Python 3 documentation, passing in the same object as the reader and writer is a security warning as it generally leads to undefined/undesired behavior. Should a developer want to use an interface for random access streams, it is recommended to use BufferedRandom instead, which creates both a reader and writer for a singular raw stream, and is generally more tailored for this purpose.