ere are a few ways to rephrase and elaborate on "involved a lot of machine learning fundamentals et'c and was intense" in around four words, focusing on different aspects: Highlighting Depth: Deep ML theory applied. (Emphasizes theoretical understanding) Core ML concepts tested. (Focuses on fundamental knowledge) Highlighting Rigor: Demanding ML principles rigorously. (Stresses high standards) Intricate ML logic challenged. (Points to complex thinking)