Boolean data and the bool() function

All objects can have a mapping to the Boolean domain of values: True and False. All of the built-in classes have this mapping defined. When we define our own classes, we need to consider this Boolean mapping as a design feature.

The built-in classes operate on a simple principle: if there's clearly no data, the object should map to False. Otherwise, it should map to True. Here are some detailed examples:

• The None object maps to False.

• For all of the various kinds of numbers, a zero value maps to False. All non-zero values are True.

• For all of the collections (including str, bytes, tuple, list, dict, set, and so on) an empty collection is False. A non-empty collection is True.

We can use the bool() function to see this mapping between object and a Boolean:

>>> red_violet= (192, 68, 143)
>>> bool(red_violet)
True
>>> empty = ()
>>> type(empty)
<class 'tuple'>
>>> bool(empty)
False

We've created a simple sequence...