绘制箱线图

def solve():
    from sklearn.datasets import load_iris
    import matplotlib.pyplot as plt
    iris = load_iris()
    plt.figure(figsize=(10, 6))
    plt.boxplot([iris.data[iris.target==i, 0] for i in range(3)], labels=iris.target_names, patch_artist=True)
    plt.xlabel('品种')
    plt.ylabel('花萼长度 (cm)')
    plt.title('三种鸢尾花花萼长度箱线图')
    plt.grid(alpha=0.3, axis='y')
    plt.show()