For the purpose of constructing a generator, the author wrote:
> In an object-oriented setting like Python or Java, streams can be constructed from an interface
Yikes. itertools was introduced in, let's see... 2003?
def int_generator():
i = 0
while True:
yield i
i += 1
for n, square in ((i, i * i) for i in int_generator()):
print(f"{n}² = {square}")
time.sleep(1)