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shared by Benjamin Bandt-Horn on 30 Dec 13 - No Cached

Comprehensions are just a simple form of iterators. Generators are just a simple form of iterators
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The first argument of every class method, including the __init__() method, is always a reference to the current instance of the class. By convention, this argument is named self.
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self is not a reserved word in Python, merely a naming convention
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To build an iterator from scratch, Fib needs to be a class, not a function.
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in most cases), __iter__() simply returns self, since this class implements its own __next__() method.
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a for loop will call this automatically, but you can also call it yourself manually
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the __next__() method raises a StopIteration exception, this signals to the caller that the iteration is exhausted. Unlike most exceptions, this is not an error; it’s a normal condition that just means that the iterator has no more values to generate. If the caller is a for loop, it will notice this StopIteration exception and gracefully exit the loop. (In other words, it will swallow the exception.)
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Do not use yield here; that’s a bit of syntactic sugar that only applies when you’re using generators. Here you’re creating your own iterator from scratch; use return instead
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raise StopIteration
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shared by Benjamin Bandt-Horn on 30 Dec 13 - No Cached

I just found xrange() (suprised I hadn't seen it before...) and added it to the above example. xrange() is an iterable version of range() which has the advantage of not prebuilding the list
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shared by Benjamin Bandt-Horn on 20 Dec 13 - No Cached

It's not an operator as such, so it doesn't really have a name, but it is defined as a "syntactic rule". So it should be called: "the keyword argument unpacking syntax"
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# usually a tuple, always an iterable*
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# usually a dict, always a mapping*
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kwargs
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args =
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*: Iterables are objects that implement the __iter__() method and mappings are objects that implement __iter__() and __getitem__()
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If you are unsure what to call a particular operator or if it is unnamed, you can always resort to Waka Waka Bang Splat as a reference to help you figure out what to call it. In this case for ** I would call it double-splat, though there are some alternate names for symbols.
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shared by Benjamin Bandt-Horn on 30 Dec 13 - No Cached

usually __iter__() just return self if you have already define the next() method (generator object)
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While you are looking at the collections module, consider inheriting from Sequence, Mapping or another abstract base class if that is more appropriate. Here is an example for a Sequence subclass:
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if hasattr(self.data[0], "__iter__": return self.data[0].__iter__() return self.data.__iter__()
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