Add even number function and its corresponding unit to main

[Luyando-Chitindi]

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Name: Checking if an integer is even solution review
code review with a checklist

Challenge chosen by: Luyando Chitindi
Assigned to: Luyando Chitindi
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The challenge I chose to solve is checking if an integer is an even number.

Behavior

Files

• The file name describes the function's behavior
• There is a module docstring in the function file
• The test file's name matches the function file name -
  /tests/test_file_name.py
• There is a module docstring in the tests file

Unit Tests

• The test class has a helpful name in PascalCase
• The test class has a docstring
• Every unit test has
  • A helpful name
  • A clear docstring
  • Only one assertion
  • There is no logic in the unit test
• All tests pass
• There are tests for defensive assertions
• There are tests for boundary cases

Function Docstring

• The function's behavior is described
• The function's arguments are described:
  • Type
  • Purpose
  • Other assumptions (eg. if it's a number, what's the expected range?)
• The return value is described
  • Type
  • Other assumptions are documented
• The defensive assertions are documented using Raises:
  • Each assumption about an argument is checked with an assertion
  • Each assertion checks for only one assumption about the argument
• Include 3 or more (passing!) doctests

The Function

• The function's name describes it's behavior
• The function's name matches the file name
• The function has correct type annotations

Strategy

Do's

• Variable names help to understand the strategy
• Any comments are clear and describe the strategy
• Lines of code are spaced to help show different stages of the strategy

Don'ts

• The function's strategy is not described in the documentation
• Comments explain the strategy, not the implementation
• The function does not have more comments than code
  • If it does, consider finding a new strategy or a simpler implementation

Implementation

• The code passes the formatting checks
• The code passes all Ruff linting checks
• The code has no (reasonable) Pylint errors
  • In code review, you can decide when fixing a Pylint error is helpful and
    when it's too restricting.
• Variables are named with snake_case
• Variable names are clear and helpful
• The code follows the strategy as simply as possible
• The implementation is as simple as possible given the strategy
• The code includes defensive assertions
• Defensive assertions include as little logic as possible

[Moealfadil]

check the py_formatting

[Luyando-Chitindi]

@Moealfadil thank you so much!
i have managed to fix that.

[Moealfadil]

nicely done!