python - Exchanging the content of 2 variables

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Exchanging the content of 2 variables

In most languages, exchanging the content of two variable involves using a temporary variable.

In Python, this can be done with multiple assignment.
"""
>>> a=3
>>> b=7
>>> (a,b)=(b,a)
>>> print a
7
>>> print b
3

In Python, tuples, lists and dictionnaries are your friends, really !

Highly recommended reading: Dive into Python (http://diveintopython.org/). The first chapter contains a nice tutorial on tuples, lists and dictionnaries. And don't forget to read the rest of the book (You can download the entire book for free).
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