Learning Python, 3rd Edition

Chapter 9. Tuples, Files, and Everything Else

This chapter rounds out our in-depth look at the core object types in Python by exploring the tuple (a collection of other objects that cannot be changed), and the file (an interface to external files on your computer). As you’ll see, the tuple is a relatively simple object that largely performs operations you’ve already learned about for strings and lists. The file object is a commonly used and full-featured tool for processing files; the basic overview of files here will be supplemented by further file examples that appear in later chapters of this book.

This chapter also concludes this part of the book by looking at properties common to all the core object types we’ve met—the notions of equality, comparisons, object copies, and so on. We’ll also briefly explore other object types in the Python toolbox; as you’ll see, although we’ve covered all the primary built-in types, the object story in Python is broader than I’ve implied thus far. Finally, we’ll close this part of the book by taking a look at a set of common object type pitfalls, and exploring some exercises that will allow you to experiment with the ideas you’ve learned.

Tuples

The last collection type in our survey is the Python tuple. Tuples construct simple groups of objects. They work exactly like lists, except that tuples can’t be changed in-place (they’re immutable), and are usually written as a series of items in parentheses, not square brackets. Although they don’t support ...