层次聚类

def solve():
    from sklearn.datasets import load_iris
    from scipy.cluster.hierarchy import linkage, dendrogram
    import matplotlib.pyplot as plt
    iris = load_iris()
    Z = linkage(____)
    plt.figure(figsize=(____, ____))
    dendrogram(____)
    plt.xlabel(____)
    plt.ylabel(____)
    plt.title(____)
    plt.show()