Custom file class

[deanhystad]

I have a special format file with a header and some content. In other languages I wrote a file subclass for reading and writing this file type. The file class has a dictionary like interface for the header and a streaming interface for reading/writing the other content. I am thinking about how to do this in Python. Could anyone point me to examples of subclassing io for reading/writing a special file format or suggest better ways to do this kind of thing in Python.