python使用model.compile方法的时候，遇到AttributeError: 'NoneType' object has no attribute 'compile'这个问题

Question

在跑《deep learning for computer vision with python》第一本第15章的mvggnet程序时候，遇到使用model.compile方法出现bug。'NoneType' object has no attribute 'compile'

import matplotlib

matplotlib.use("Agg")

from sklearn.preprocessing import LabelBinarizer
from sklearn.metrics import classification_report
from pyimagesearch.nn.conv import minivggnet
from keras.optimizers import SGD
from keras.datasets import cifar10
import matplotlib.pyplot as plt
import numpy as np
import argparse

ap = argparse.ArgumentParser()
ap.add_argument("-o", "--output", required=True,
                help="path to the output loss/accuracy plot")
args = vars(ap.parse_args())

print("[INFO] loading CIFAR-10 data...")
((trainX, trainY), (testX, testY)) = cifar10.load_data()
trainX = trainX.astype("float") / 255.0
testX = testX.astype("float") / 255.0

lb = LabelBinarizer()
trainY = lb.fit_transform(trainY)
testY = lb.transform(testY)

labelNames = ["airplane", "automobile", "bird", "cat", "deer",
              "dog", "frog", "horse", "ship", "truck"]

print("[INFO] compiling model...")
opt = SGD(lr=0.01, decay=0.01 / 40, momentum=0.9, nesterov=True)
model = minivggnet.build(width=32, height=32, depth=3, classes=10)
model.compile(loss='categorical_crossentropy', optimizer=opt,
              metrics=["accuracy"])

print("[INFO] training network...")
H = model.fit(trainX, trainY, validation_data=(testX, testY), batch_size=64,
              epydoc=40, verbose=1)

print("[INFO] evaluating network...")
predictions = model.predict(testX, batch_size=64)
print(classification_report(testY.argmax(axis=1),
                            predictions.argmax(axis=1),
                            target_names=labelNames))

plt.style.use("ggplot")
plt.figure()
plt.plot(np.arange(0, 40), H.history["loss"], label="train_loss")
plt.plot(np.arange(0, 40), H.history["val_loss"], label="val_loss")
plt.plot(np.arange(0, 40), H.history["accuracy"], label="train_accuracy")
plt.plot(np.arange(0, 40), H.history["val_accuracy"], label="val_accuracy")
plt.title("Training Loss and Accuracy on CIFAR-10")
plt.xlabel("Epoch #")
plt.ylabel("Loss/Accuracy")
plt.legend()
plt.savefig(args["output"])

AttributeError: 'NoneType' object has no attribute 'compile'

有无帅哥美女帮忙解决一下问题哭了

我想要达到的结果