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The ultimate guide to coding with Python
Pi 2
projects
inside
Learn to use Pythont Program games t Get creative with Pi



Welcome to
PyThethon
Python is an incredibly versatile, expansive language which, due to its


similarity to everyday
language, is surprisingly easy to learn even for inexperienced programmers.
It has seen a
huge increase in popularity since the release and rise of the Raspberry Pi, for
which Python
is the officially recognised programming language. In The Python Book,
you’ll find plenty
of creative projects to help you get to grips with the combination of your
Raspberry Pi and
Python’s powerful functionality, but there are also plenty of tutorials that
focus on Python’s
effectiveness away from the Raspberry Pi. You’ll learn all about how to code
with Python

from the very beginning with our comprehensive masterclass, then go on to
complete
tutorials to consolidate your skills and become fluent in the language while
also improving
your computing experience. You’ll learn how to make Python work for you
with tutorials
on coding with Django, Flask, Pygame and even more useful third-party
applications and
frameworks. Get ready to become a true Python expert with the wealth of
information
contained within these pages.



PyThethon
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The Python Book © 2015 Imagine Publishing Ltd

ISBN 9781785460609


Part of the
bookazine series


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Get started with Python
Get started
Python


with
Always wanted to have a go at
programming? No more excuses,
because Python is the perfect way to get started!
Python is a great programming language for libraries to create a windowed

application, or you could both beginners and experts. It is designed with
try something a little more ambitious like an app such
code readability in mind, making it an excellent
as creating one using Python’s Bluetooth and Input
choice for beginners who are still getting used to
libraries to capture the input from a USB keyboard and
various programming concepts.
relay the input events to an Android phone.
The language is popular and has plenty of libraries
For this tutorial we’re going to be using Python 2.x
available, allowing programmers to get a lot done with
since that is the version that is most likely to be installed
relatively little code.
on your Linux distribution.
You can make all kinds of applications in Python:
In the following tutorials, you’ll learn how to create


you could use the Pygame framework to write
popular games using Python programming. We’ll also
simple 2D games, you could use the GTK
show you how to add sound and AI to these games.
8 The Python Book


Get started with Python
The Python Book 9


Get started with Python

Hello World
Variables and data types


Let’s get stuck in, and what better way than with the A variable is a name in
source code that is associated with an programmer’s best friend, the ‘Hello
World’ application! Start
area in memory that you can use to store data, which is then
by opening a terminal. Its current working directory will be your
called upon throughout the code. The data can be one of many
home directory. It’s probably a good idea to make a directory for
types, including:
the fi les we’ll be creating in this tutorial, rather than having them
loose in your home directory. You can create a directory called
Python using the command mkdir Python. You’ll then want to
Integer
Stores whole numbers
change into that directory using the command cd Python.
The next step is to create an empty fi le using the command
Float
Stores decimal numbers
‘touch’ followed by the fi lename. Our expert used the command
Boolean
Can have a value of True or False
touch hello_world.py. The fi nal and most important part of


String
Stores a collection of characters. “Hello
setting up the fi le is making it executable. This allows us to run

World” is a string
code inside the hello_world.py fi le. We do this with the command
chmod +x hello_world.py. Now that we have our fi le set up, we
can go ahead and open it up in nano, or any text editor of your
As well as these main data types, there are sequence types
choice. Gedit is a great editor with syntax highlighting support
(technically, a string is a sequence type but is so commonly used
that should be available on any distribution. You’ll be able to
we’ve classed it as a main data type):
install it using your package manager if you don’t have it already.
List
Contains a collection of data in a specifi c order
[liam@liam-laptop ~]$ mkdir Python
[liam@liam-laptop ~]$ cd Python/
Tuple
Contains a collection immutable data in a
specifi c order