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Mastering Python: Annotations, Errors and Environment
course content

Course Content

Mastering Python: Annotations, Errors and Environment

Mastering Python: Annotations, Errors and Environment

1. Annotations
What are Annotations?Variable AnnotationReturn AnnotationDocstringChallenge: Annotate the Functionhelp()
2. Function Arguments in Details
Positional ArgumentsOptional ArgumentsArbitrary Arguments (*args)Arbitrary Keyword Arguments (**kwargs)UnpackingChallenge: Snake and Sum
3. Error Handling
What are Errors?ExamplesRaisingHandlingDetailed exceptChallenge: Safely Auth
4. Virtual Environment
What is Virtual Environment?Creating a Virtual EnvironmentProject RequirementsVirtual Environment in IDE: PyCharmVirtual Environment in IDE: VS Code

book
Raising

Let's learn how to raise an error.

Errors can be raised using the raise keyword:


              
1

            
raise TypeError
copy

The TypeError in the example above was raised without a message.

To output an error message, you can pass a string inside the parentheses () after the error object:


              
1

            
raise ValueError("Wrong value!")
copy
Task
test

Swipe to show code editor

You have implemented the perimeter() function that returns the triangle perimeter. This function receives the sides of a triangle (a, b, and c). You need to add error raising to this function.

  1. All received sides should be int or float data type. In another case, the function should raise the TypeError with the message "All sides should be int or float type".

  2. In a triangle, all sides should have a length greater than 0. In other cases, the function should raise the ValueError with the message "All sides should be greater than 0".

  3. In a triangle, the sum of two sides must always be greater than the third side (otherwise, the two sides would not reach each other through the third side). Therefore, if one of the received sides is greater than the sum of the other two, the program must raise the ValueError with the message "It's not a triangle".

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Section 3. Chapter 3
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book
Raising

Let's learn how to raise an error.

Errors can be raised using the raise keyword:


              
1

            
raise TypeError
copy

The TypeError in the example above was raised without a message.

To output an error message, you can pass a string inside the parentheses () after the error object:


              
1

            
raise ValueError("Wrong value!")
copy
Task
test

Swipe to show code editor

You have implemented the perimeter() function that returns the triangle perimeter. This function receives the sides of a triangle (a, b, and c). You need to add error raising to this function.

  1. All received sides should be int or float data type. In another case, the function should raise the TypeError with the message "All sides should be int or float type".

  2. In a triangle, all sides should have a length greater than 0. In other cases, the function should raise the ValueError with the message "All sides should be greater than 0".

  3. In a triangle, the sum of two sides must always be greater than the third side (otherwise, the two sides would not reach each other through the third side). Therefore, if one of the received sides is greater than the sum of the other two, the program must raise the ValueError with the message "It's not a triangle".

Switch to desktopSwitch to desktop for real-world practiceContinue from where you are using one of the options below
Everything was clear?

How can we improve it?

Thanks for your feedback!

Section 3. Chapter 3
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