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Explain the advantages of reversed.
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@ -34,7 +34,7 @@ and returns an iterator that returns the elements of the sequence
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in reverse order.
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\begin{verbatim}
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>>> for i in reversed([1,2,3]):
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>>> for i in reversed(xrange(1,4)):
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... print i
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...
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3
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@ -42,9 +42,12 @@ in reverse order.
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1
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\end{verbatim}
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Compared to extended slicing, \code{range(1,4)[::-1]}, \function{reversed()}
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is easier to read, runs faster, and uses substantially less memory.
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Note that \function{reversed()} only accepts sequences, not arbitrary
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iterators. If you want to reverse an iterator, convert it to
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a list or tuple with \function{list()} or \function{tuple()}.
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iterators. If you want to reverse an iterator, first convert it to
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a list with \function{list()}.
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\begin{verbatim}
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>>> input = open('/etc/passwd', 'r')
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