In the Python tutorial, in "9. Classes", in "9.10 Generator expression", a list of sample generator expressions used as arguments to functions is given. However, one of the examples isn't a generator expression, it's a set comprehension.

sine_table = {x: sin(x*pi/180) for x in range(0, 91)}

Perhaps this used to be a call to set() and was mistakenly converted?

Correction: it's a dictionary comprehension, and it did indeed used to be a call to dict() in the 2.7 documentation.

This example is also in 2.7 
https://docs.python.org/2.7/tutorial/classes.html#generator-expressions

-> I add 2.7

I agree that 2.7 is incorrect also, 2.7 has dict comprehensions also so there's no reason to pass a generator expression to dict().

I add 3.4 and 3.8 because they also have the problem.

New changeset ab328756d7fd969ee4882458b07892dff135013c by Xiang Zhang (Stéphane Wirtel) in branch 'master':
bpo-32722: Remove useless example in the Classes tutorial (#5446)
https://github.com/python/cpython/commit/ab328756d7fd969ee4882458b07892dff135013c

I treat it as an enhancement so only merge it into 3.8. Thanks Soothsayer for the report and Stéphane for the patch!