Test-Driven Development
1. Create a new test that covers a feature to be implemented. The test is expected to fail at its first execution because the feature has yet to be implemented.
2. Run all tests and make sure the new test fails.
3. Write code to make the new test pass.
4. Run all tests and make sure they all pass.
5. Refactor the code that is newly written and make sure the tests still pass.
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