''' Iterables are any object that, when the iter() method is called (implicitly or not), returns an iterator (an object with a __next__() method). Sometimes, these objects can even be the same (as is the case with this example). ''' ''' This class is an iterable class, because it contains an __iter__() method which returns an iterator (in this case, itself). Each time the next() method is called, a value is generated. These values are lazily loaded, like generators, but they are stored in memory as part of a class instance attribute. ''' class iterable: def __init__(self, i, n): self.i = i self.n = n def __iter__(self): # <-- makes this an iterable, and returns an iterator (itself) return self def __next__(self): if self.i < self.n: tmp = self.i self.i += 1 return tmp**2 else: raise StopIteration y = iterable(1, 10) for j in y: # print(y.i) <-- this line prints the value of i when the function returns print(j)