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Wikipedia results
1.Iterator
iterable (but not necessarily indexable) object. Several languages, such as Perl and Python, implement streams as iterators. In Python, iterators are objects
https://en.wikipedia.org/wiki/Iterator
2.Generator (computer programming)
the right way. For example, a ranged loop like for x = 1 to 10 can be implemented as iteration through a generator, as in Python‘s for x in range(1, 10)
https://en.wikipedia.org/wiki/Generator (computer programming)