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Code reviewMedium
Question
Review this Python model-evaluation routine.
It always selects max_depth=None with accuracy 1.0. Is that the best model?
What a strong answer looks like
Separate real bugs from style. Rank issues by severity, point at the root cause rather than the symptom, and suggest a concrete fix — specific and kind.
Learn the concepts
from sklearn.tree import DecisionTreeClassifierfrom sklearn.metrics import r2_score, accuracy_score def pick_best_depth(X, y, depths=(2, 5, 10, None)): best, best_score = None, -1 for d in depths: model = DecisionTreeClassifier(max_depth=d, random_state=0) model.fit(X, y) score = accuracy_score(y, model.predict(X)) # how good is it? print(d, score) if score > best_score: best, best_score = d, score print("best depth:", best) return bestRun or narrate your approach, then ask the coach.