You will need to install a Python distribution on your local machine, which should have at least 4 GB of memory. For Chapter 9, Performing Network Automation with Python and Ansible, you will also need to install Ansible and have a local network configured or local virtual machines with Python installed for executing Ansible scripts. For Chapter 11, Designing Servers and Asynchronous Programming, examples involving Celery also need to be executed on a localhost Redis server.

In this book, all examples are available for execution in Python version 3.7 and are compatible with the Windows and Unix operating systems.

You can download the example code files for this book from your account at www.packt.com. If you purchased this book elsewhere, you can visit www.packt.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.packt.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/Learning-Python-Networking-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!

We also provide a PDF file that has color images of the screenshots/diagrams used in this book. You can download it here: https://www.packtpub.com/sites/default/files/downloads/9781789958096_ColorImages.pdf.

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: "You can find the following code in the urllib_exceptions.py file."

A block of code is set as follows:

# setup crawler
from scrapy.crawler import CrawlerProcess
crawler = CrawlerProcess(settings)
# define the spider for the crawler
crawler.crawl(MySpider())
# start scrapy
print("STARTING ENGINE")
crawler.start()

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

# setup crawler
from scrapy.crawler import CrawlerProcess
crawler = CrawlerProcess(settings)
# define the spider for the crawler
crawler.crawl(MySpider())
# start scrapy
print("STARTING ENGINE")
crawler.start()

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

pip install lxml

Bold: Indicates a new term, an important word, or words that you see on screen. For example, words in menus or dialog boxes appear in the text like this. Here is an example: "Among the available plugins for Firefox, we can highlight the HTTP Header Live add-ons."