Book Image

The Python Apprentice

By : Robert Smallshire, Austin Bingham
Book Image

The Python Apprentice

By: Robert Smallshire, Austin Bingham

Overview of this book

Experienced programmers want to know how to enhance their craft and we want to help them start as apprentices with Python. We know that before mastering Python you need to learn the culture and the tools to become a productive member of any Python project. Our goal with this book is to give you a practical and thorough introduction to Python programming, providing you with the insight and technical craftsmanship you need to be a productive member of any Python project. Python is a big language, and it’s not our intention with this book to cover everything there is to know. We just want to make sure that you, as the developer, know the tools, basic idioms and of course the ins and outs of the language, the standard library and other modules to be able to jump into most projects.
Table of Contents (21 chapters)
Title Page
Credits
About the Authors
www.PacktPub.com
Customer Feedback
Preface
12
Afterword – Just the Beginning

set – an unordered collection of unique elements


The set data type is an unordered collection of unique elements. The collection is mutable insofar as elements can be added and removed from the set, but each element must itself be immutable, very much like the keys of a dictionary.

Sets are unordered groups of distinct elements as illustrated in the following image:

Figure 5.21: Set

Sets have a literal form very similar to dictionaries, again delimited by curly braces, but each item is a single object, rather than a pair joined by a colon:

>>> p = {6, 28, 496, 8128, 33550336}

Note that like a dictionary, the set is unordered:

>>> p
{33550336, 8128, 28, 496, 6}

Of course, sets have type set:

>>> type(p)
<class 'set'>

 

The set constructor

Recall that somewhat confusingly, empty curly braces create an empty dictionary, rather than an empty set:

>>> d = {}
>>> type(d)
<class 'dict'>

To create an empty set we must resort to the set() constructor:

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