Inheritance and Overriding __init__ in python

The book is a bit dated with respect to subclass-superclass calling. It’s also a little dated with respect to subclassing built-in classes.

It looks like this nowadays:

class FileInfo(dict):
    """store file metadata"""
    def __init__(self, filename=None):
        super(FileInfo, self).__init__()
        self["name"] = filename

Note the following:

1. We can directly subclass built-in classes, like dict, list, tuple, etc.

2. The super function handles tracking down this class’s superclasses and calling functions in them appropriately.