reading help() - newbie question

[Payal]

Hi,
I am trying to learn Python (again) and have some basic doubts which I
hope someone in the list can address. (English is not my first language and I
have no CS background except I can write decent shell scripts)

When I type help(something) e.g. help(list), I see many methods like,
__methodname__(). Are these something special? How do I use them and why
put "__" around them?

One more simple query. Many times I see something like this,
|      D.iteritems() -> an iterator over the (key, value) items of D
What is this iterator they are talking about and how do I use these
methods because simly saying D.iteritems() does not work?

Thanks a lot in advance.
With warm regards,
-Payal
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