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4.9.1.4 StreamReaderWriter Objects

The `StreamReaderWriter` allows wrapping streams which work in both read and write modes.

The design is such that one can use the factory functions returned by the `lookup()` function to construct the instance.

class `StreamReaderWriter`( | stream, Reader, Writer, errors)

  Creates a `StreamReaderWriter` instance. stream must be a file-like object. Reader and Writer must be factory functions or classes providing the `StreamReader` and `StreamWriter` interface resp. Error handling is done in the same way as defined for the stream readers and writers.

`StreamReaderWriter` instances define the combined interfaces of `StreamReader` and `StreamWriter` classes. They inherit all other methods and attribute from the underlying stream.