Python 3 Object-Oriented Programming - Third Edition

Dictionary use cases

Dictionaries are extremely versatile and have numerous uses. There are two major ways that dictionaries can be used. The first is dictionaries where all the keys represent different instances of similar objects; for example, our stock dictionary. This is an indexing system. We use the stock symbol as an index to the values. The values could even have been complicated, self-defined objects that had methods to make buy and sell decisions or set a stop-loss, rather than our simple tuples.

The second design is dictionaries where each key represents some aspect of a single structure; in this case, we'd probably use a separate dictionary for each object, and they'd all have similar (though often not identical) sets of keys. ...