Wrapping a file function

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Wrapping a file function

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Last edited May 3, 2014

Created on Apr 30, 2014

This example demonstrates a Python decorator that transparently manages file handles for functions expecting file objects. The `wrap_file_function` class wraps a function so it can accept either a file handle or a filename string, automatically opening and closing the file when a string is passed. The code shows usage across writing, reading, and multiple-file scenarios, including error handling when a nonexistent file is read. Using Python's built-in `open`, `isinstance`, and function wrapping, it illustrates how decorators can standardize file I/O patterns.

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