https://docs.python.org/3/faq/programming.html#how-do-i-iterate-over-a-sequence-in-reverse-order
It contains the following example:
for x in reversed(sequence):
... # do something with x ...
With the note:
> This won’t touch your original sequence, but build a new copy with reversed order to iterate over.
The part about "build a new copy" is not correct in a sense that `reversed` just returns an iterator over the original sequence. This has mainly two consequences:
1. It can't be indexed, i.e. `reversed(sequence)[0]` doesn't work.
2. Changing the original sequence after `r = reversed(sequence)` has been constructed, is reflected in `r` when iterating over it.
So the sentence should be changed into something like:
> This creates an iterator object that can be used to iterate over the original sequence in reverse order.
Then for the second example about `sequence[::-1]` it would be good to mention the difference to `reversed`, namely that this version *does* create a copy of the original list (in reverse order). It could also be used as an opportunity to show how to reverse a string, since that is a very popular question on StackOverflow.
Also the various mentions of Python versions 2.3 and 2.4 seem strange since this is documentation about Python 3 and those version are anyway very old. So they should be left out as well.
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