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If statements in Python can be extended to test multiple conditions using elif.

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Let's go ahead and make a working copy of conditionals.py, call it

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conditionals-working.py, and we'll go ahead and open our working copy and

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define a variable here.

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We'll say if v is == to one, print v is one elif v == two, print v is two, and we could do as many of

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these as we wanted to.

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So, when we save this and run it, you'll notice we get v is one. And if we change this

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one to, say, a three, save that and run it, then we get v is three, but if we make

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this a seven, then save that and run it, nothing at all happens.

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Now, if you want to have a default case, you can simply say, else:

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and this still gets executed if none of the conditions turn out to be true.

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Say, print v is some other thing,

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and save that and run it, and we get V is some

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other thing, because v is seven.

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So, the thing to understand about this is that only one of these suites is ever

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going to be executed.

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So, you have if, and an expression that evaluates to true or false, and a colon,

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and a suite, and then with each of the elifs, you also have an expression that

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evaluates to true or false, and a colon, and a suite.

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Only one of these suites is ever going to get executed, and that's the purpose of elif.

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It allows you to have several different conditions that get evaluated, and only

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one of them will ever get executed.

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And then finally, the else clause is executed in the event that none of the

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conditions is true, but again, only one of these suites will ever be executed.