Consider the following Python code. What is the output?

>>> a, *b, c = (1, 2, 3, 4, 5)
>>> print(b)

The answer is [2, 3, 4].

Python uses a special syntax to pass optional arguments (*args) for tuple unpacking. This means that we can have an optional number of elements in the middle of a tuple.

We can also use the more general format where optional arguments, or varargs, appear at the end of a statement:

>>> a, b, *c = (1, 2, 3, 4, 5)
>>> print(b) # 2
>>> print(c) # [3, 4, 5]

This special syntax is more commonly used in function calls alongside the (**kwargs) syntax for keyword arguments. You can learn more about *args and **kwargs in this tutorial).

Personally, I find it helpful to remember that generally speaking arguments follow the order (args, name=args, *args, **args). See more in the official docs here.

Want to improve your Python? I have a list of recommended Python books.