[Python] try-finally in Python 3 generator

I have met a snippet of Python 3 code:

def gen():
try:
while True:
yield 1
finally:
print("stop")

print(next(gen()))


After I run it, I thought at first that the output should be:

1


But actually the result is:

stop
1


How can this happen? What happened under the hood?

If I run for i in gen(): print(i), there will be an infinite loop which is what I expected. What is the difference between for and next here?

Continue reading...