逻辑回归

def solve():
    import matplotlib
    matplotlib.use(____)
    import matplotlib.pyplot as plt
    from sklearn.datasets import load_iris
    from sklearn.tree import DecisionTreeClassifier, plot_tree
    iris = load_iris()
    X = iris.data
    y = iris.target
    model = DecisionTreeClassifier(____).fit(____)
    plt.figure(figsize=(____, ____))
    plot_tree(____)
    plt.tight_layout()
    plt.show()
    print(model.get_depth())