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3.7 UserDict -- Class wrapper for dictionary objects

Note: This module is available for backward compatibility only. If you are writing code that does not need to work with versions of Python earlier than Python 2.2, please consider subclassing directly from the built-in dict type.

This module defines a class that acts as a wrapper around dictionary objects. It is a useful base class for your own dictionary-like classes, which can inherit from them and override existing methods or add new ones. In this way one can add new behaviors to dictionaries.

The UserDict module defines the UserDict class:

class UserDict([initialdata])

Class that simulates a dictionary. The instance's contents are kept in a regular dictionary, which is accessible via the data attribute of UserDict instances. If initialdata is provided, data is initialized with its contents; note that a reference to initialdata will not be kept, allowing it be used used for other purposes.

In addition to supporting the methods and operations of mappings (see section 2.2.7), UserDict instances provide the following attribute:

data

A real dictionary used to store the contents of the UserDict class.

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Python Library Reference

Previous: 3.6 types Up: 3. Python Runtime Services Next: 3.8 UserList

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Release 2.2.2, documentation updated on October 14, 2002.