python console

>>> def foo():
...     try:
...         print('start')
...         yield 1
...         yield 2
...         print('bye')
...     except GeneratorExit:
...         print('forced exit')
... 
>>> f = foo()
>>> next(f)
start
1
>>> next(f)
2
>>> next(f)
bye
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
StopIteration
>>> 
>>> f = foo()
>>> next(f)
start
1
>>> next(f)
2
>>> del f
forced exit