You are encouraged to follow the examples in this book. In order to do so, you will need a computer, an internet connection, and a browser. The book is written in Python 3.7, but it should also work, for the most part, with any recent Python 3.* version. I have given guidelines on how to install Python on your operating system. The procedures to do that change all the time, so you will need to refer to the most up-to-date guide on the Web to find precise setup instructions. I have also explained how to install all the extra libraries used in the various examples and provided suggestions if the reader finds any issues during the installation of any of them. No particular editor is required to type the code; however, I suggest that those who are interested in following the examples should consider adopting a proper coding environment. I have given suggestions on this matter in the first chapter.

You can download the example code files for this book from your account at www.packtpub.com. If you purchased this book elsewhere, you can visit www.packtpub.com/support and register to have the files emailed directly to you.

You can download the code files by following these steps:

1. Log in or register at www.packtpub.com.
2. Select the SUPPORT tab.
3. Click on Code Downloads & Errata.
4. Enter the name of the book in the Search box and follow the onscreen instructions.

Once the file is downloaded, please make sure that you unzip or extract the folder using the latest version of:

• WinRAR/7-Zip for Windows
• Zipeg/iZip/UnRarX for Mac
• 7-Zip/PeaZip for Linux

The code bundle for the book is also hosted on GitHub at https://github.com/PacktPublishing/Learn-Python-Programming-Second-Edition. In case there's an update to the code, it will be updated on the existing GitHub repository.

We also have other code bundles from our rich catalog of books and videos available at https://github.com/PacktPublishing/. Check them out!

There are a number of text conventions used throughout this book.

CodeInText: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: "Within the learn.pp folder, we will create a virtual environment called learnpp."

A block of code is set as follows:

# we define a function, called local
def local():
    m = 7
    print(m)

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

# key.points.mutable.assignment.py
x = [1, 2, 3]
def func(x):
    x[1] = 42  # this changes the caller!
    x = 'something else'  # this points x to a new string object

Any command-line input or output is written as follows:

>>> import sys
>>> print(sys.version)

Bold: Indicates a new term, an important word, or words that you see onscreen. For example, words in menus or dialog boxes appear in the text like this. Here is an example: "To open the console in Windows, go to the Start menu, choose Run, and type cmd."