Summary

We've covered a lot of ground in this chapter, but you should now be able to start making real use of the web APIs that you encounter.

We looked at XML, 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 also looked at how the XPath query language can be used efficiently for extracting information from documents.

We looked at the Amazon S3 service and wrote a client that lets us perform basic operations, such as creating buckets, and uploading and downloading files through the S3 REST API. We learned about setting access permissions and setting content types, such that the files work properly in web browsers.

We looked at 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 world clock service, through which we learned how to read and process tweets...