WEBVTT

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When you are using variables in Python, you need to adhere to a few rules and guidelines.

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Breaking some of these rules will cause errors.

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Other guidelines just help you write code that's easier to read and understand, so be sure to keep

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these rules so.

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Variable names.

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Variable names.

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So variable names can contain only letters, numbers and underscores.

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Here, variable names can contain only letters.

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Numbers.

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And underscores.

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They can start with a letter or an underscore, but not with a number.

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So as I said, variable names cannot start with number.

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So here, let's try this one.

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Var.

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Here.

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As you can see here, Rozelle.

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Rozelle.

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And in the end of statement expected.

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So as you can as you can see here, we are getting an error because variable names cannot start with

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a number.

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So, for example, you can also call this message one, it's okay, but you cannot call one message.

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Actually, let's try this here.

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Message one.

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As you can see, we are getting no errors.

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But you cannot.

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Right?

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Name your variable one message or one message without underscore.

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Here and spaces are not allowed in variable names.

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So here, message here.

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Let's write this.

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My message.

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And here this is a this is okay variable name, but we make space here.

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We will get an error.

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Instead of using space.

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You can also use underscores and you will get no errors here.

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Avoid using Python keywords and function names as variable names.

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For example.

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Do not use the word print as a variable name.

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Python has a reserved for a particular programming and programmatic purpose.

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And the variable names should not be short but descriptive.

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For example, the name is better than N right and the student name here.

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Student name is better than student name is better than s n here.

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Right.

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So.

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And name length.

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Name length is better than length.

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Length.

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Of length.

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A person's.

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Person's name.

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And also be careful when using the lowercase letter L and uppercase letter L, because they will.

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They could be confused with the numbers one and zero.

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It can take some practices to learn how to create good variable names, especially as your programs

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become more interesting and complicated as you write more programs and start to read through other people's

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code, you will get better at coming up with meaningful names.