混淆矩阵可视化

def solve():
    import pandas as pd
    import matplotlib.pyplot as plt
    from sklearn.neighbors import KNeighborsClassifier
    from sklearn.metrics import confusion_matrix
    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(____)
    knn = KNeighborsClassifier(____)
    knn.fit(____)
    y_pred = knn.predict(____)
    cm = confusion_matrix(____)
    plt.imshow(____); plt.colorbar(); plt.title(____)
    plt.xlabel(____); plt.ylabel(____); plt.show()
    print("____".join("____".join(str(____) for x in row) for row in cm))