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If statements allow you to write programs that can make decisions during runtime, depending on data

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in the condition that she said so she can see in the Python three documentation here, there is a little

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example that shows how to use the if statement and its variations so you can set multiple conditions

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during the decision making process.

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So let's have a look at this example here, which stems from the example in the documentation.

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What I've got in the beginning is an input function that presents a prompt to the user in the show for

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the user to type in a number or to provide an entry.

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Then, of course, the I.A. casting function so that Python will try to convert whatever the user typed

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into a number to down here in lines seven to 14 of got the if statement with a couple of variations.

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So the first thing is that the if statement is going to do is to compare whatever the user has typed

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them against numerical one.

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And if that is true, that type of condition is denoted by the that will equal marks.

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A double equals is the equality operator is not the assignment operator.

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Then Python is going to print out this message one as a word.

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If this comparison turns out to be false, therefore is not one, then Python is going to go into valuate

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the second condition.

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So the second condition, again, is trying to check to see if the number that I typed is too.

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And if it is true, it's going to print out to as they would otherwise, it is going to evaluate the

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third and the next condition.

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Now, the last one is the fallback.

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The last condition is ls will only fire and become true.

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So there's no operator here, there's no boolean operator for truthfulness.

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It is going to fire if none of the above, none of the previous conditions has fired.

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And therefore in this case, if I type anything else other than one of these three options, Python

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is going to print out something else.

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I've written this into a Python file program instead of running this example in the show like I've done

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with previous examples, because quite a few lines of code here, it's just easier to run it repeatedly

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by clicking on the green button.

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You can click on the green button to run it and I'm going to type, say, two, and the correct answer

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comes back.

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What happened is that the first condition was attenuated and it came out false.

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The second condition was a value added.

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It came out true.

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Number 10 line was evaluated, printed out the number two in a word, and then the program finished.

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Let's do this one more time.

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This time I'm going to type in five and five means something else.

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So none of the first three conditions were true.

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So we went down to the fallback condition, which was line 14.

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Of course, for these comparison operators, you can use other as well, not just the equality operator.

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Of course, when you make a comparison as part of an if statement, you're not confined to testing for

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a quality, you can test for a lot of other things.

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You can have a look at the value comparisons section of the Python three, the limitation.

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And you can see that operators such as these are also available to less than greater than is equal operator

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quality that we've been playing with.

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And then you've got a bunch of others as well.

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So if you want to know exactly what kind of value comparisons are possible, have a look at this documentation

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here.

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And it's a lot of information and examples that can help you with this.

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And of course, remember that you can also use a string of comparison operators to, for example, you

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can say something like this.

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So what this is going to do now is going to check whether this is true and this is true, and if both

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of these two expressions and comparisons are true, then the whole expression will become true.

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So you can make combinations as well.

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And has any number of comparisons evaluated as part of a single statement.