In this section, you’ll learn the basics of functional programming in Python and how to use the
filter() function to transform data structures.
You’ll take the example data set represented with an immutable data structure from the previous section. Then you’ll create a filtered down version of the same data using Python’s built-in
filter() function, which is one of the functional programming primitives (or building blocks) available in Python. It’s useful in a number of contexts.
Later in this section, you’ll also see how
filter() relates to list comprehensions and generator expressions in Python, and how using these is arguably more Pythonic than relying on plain