Value Get Lost In Python Generator/coroutine

I was looking at http://www.dabeaz.com/coroutines/, which I am finding very interesting, but in an example there is a behavior I do not understand. In the bogus.py example, reporte

Solution 1:

The 3 was returned from .send(), but discarded. The generator produces 5, 3, 2, 1, 0; but because the 3 is returned to the .send() call you don't see that value printed. The for loop never gets to see it.

What happens is this:

• first time the for loop calls next() on the generator, the code advances until 5 is yielded.
• x == 5 is True, so c.send(3) is called. The code advances through the generator function, and newvalue is set to 3.
• The generator does not pause there, it now has control. The generator runs through the while loop and comes back to the (yield n) expression. 3 is yielded. It becomes the return value for c.send(3). The return value is discarded here.
• The for loop continues, calls next() again. The generator is continued again with yield returning None, loops round to n -= 1 and yielding 2.
• The for loop continues to call next() on the generator, 1 and 0 are yielded, the generator ends.

Qouting from the generator.send() documentation:

Resumes the execution and “sends” a value into the generator function. The value argument becomes the result of the current yield expression. The send() method returns the next value yielded by the generator, or raises StopIteration if the generator exits without yielding another value.

Emphasis mine.