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Other Iterator Topics

We’ll learn more about both list comprehensions and iterators in Chapter 20, in conjunction with functions, and again in Chapter 29 when we study classes. As you’ll see later:

 

User-defined functions can be turned into iterable generator functions, with yield statements.List comprehensions morph into iterable generator expressions when coded in parentheses.User-defined classes are made iterable with __iter__ or __getitem__ operator overloading.

In particular, user-defined iterators defined with classes allow arbitrary objects and operations to be used in any of the iteration contexts we’ve met here.