Starting g1
g1 received 1
Starting g2
Yielded g2 spam
g2 received 2
Traceback (most recent call last):
  File "test7.py", line 28, in <module>
    y = g.send(x)
  File "test7.py", line 9, in g1
    yield from g2()
  File "test7.py", line 18, in g2
    raise ValueError("hovercraft is full of eels")
ValueError: hovercraft is full of eels