One use case for this notation is that it allows pure Python functions
to fully emulate behaviors of existing C coded functions. For example,
-the built-in :func:`pow` function does not accept keyword arguments::
+the built-in :func:`divmod` function does not accept keyword arguments::
- def pow(x, y, z=None, /):
- "Emulate the built in pow() function"
- r = x ** y
- return r if z is None else r%z
+ def divmod(a, b, /):
+ "Emulate the built in divmod() function"
+ return (a // b, a % b)
Another use case is to preclude keyword arguments when the parameter
name is not helpful. For example, the builtin :func:`len` function has