What does enumerate() mean?

Question

What does for row_number, row in enumerate(cursor): do in Python?

What does enumerate mean in this context?

Answer 1

It's a builtin function that returns an object that can be iterated over. See the documentation.

In short, it loops over the elements of an iterable (like a list), as well as an index number, combined in a tuple:

for item in enumerate(["a", "b", "c"]):
    print item

prints

(0, "a")
(1, "b")
(2, "c")

It's helpful if you want to loop over a sequence (or other iterable thing), and also want to have an index counter available. If you want the counter to start from some other value (usually 1), you can give that as second argument to enumerate.