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Practical Dependency Injection in Python

One of my favorite job interview questions is this:

Write a function that returns tomorrow’s date

This looks innocent enough for someone to suggest this as a solution:

This will work, but there is a followup question:

How would you test this function?

Before you move on…. take a second to think about your answer.

Photo by Pedro Figueras

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Originally published at on June 1, 2020.

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