In this chapter, we reviewed the JSON data format, how to convert Python objects into the JSON data format, and how to convert them back to Python objects. We then explored the Twitter API and wrote an on-demand search service using tag names. We also explored other modules, such as Tweepy, which is used for processing tweets in real time.

We learned about XML, and how to construct documents, parse them, and extract data from them by using the ElementTree API. We looked at both the Python ElementTree implementation and lxml. We looked at the Amazon S3 service and wrote a client that lets us perform basic operations, such as listing and creating buckets, and uploading and downloading files through the S3 REST API and the Boto package. 

In the next chapter, we will review the web scraping process as a technique for extracting information from websites. We will use Python packages such as BeautifulSoup and Scrapy for this purpose.