{i: i*2 for i in range(10)} # {0: 0, 1: 2, ..., 9: 18}
(x+5 for x in range(0, 10)) # (5, 6, ..., 14) -> Generator
(x+5 for x in range(0, 10)) # (5, 6, ..., 14) -> Iterator
```
```python
@ -818,7 +818,7 @@ lock.release()
Itertools
---------
**Every function returns a generator and can accept any collection. If you want to print an output of generator, as in examples, you need to pass it to the list() function.**
**Every function returns an iterator and can accept any collection and/or iterator. If you want to print the iterator, you need to pass it to the list() function.**