决策树深度控制

def solve():
    import pandas as pd
    from sklearn.tree import DecisionTreeClassifier
    from sklearn.model_selection import train_test_split
    df = pd.read_csv(____)
    X = df.drop(____); y = df["____"]
    X_train, X_test, y_train, y_test = train_test_split(____)
    results = []
    for d in [____, ____, ____, None]:
        tree = DecisionTreeClassifier(____).fit(____)
        results.append(____)
    print("____".join(____))