It is important to be able to write unit testing for your smart contracts, especially when you will write long and complex protocols which have to be tested deeply.
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Thanks but my question is: maybe I should pause the course for a moment, train myself in backend and be back to the class stronger?
Unit testing is not backend, if you feel like you should take a break and go deep into the basics you can surely do it although I think that, starting with the easy People.sol project and testing that one is the best training that you can get
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