ImportError: невозможно импортировать имя '_validate_lengths'

Я начал изучать Tensorflow. Я использую Pycharm, и моя среда — Ubuntu 16.04. Я следую руководство. Я перекрестно проверяю число. Это актуально. Я не знаю причину этой ошибки.

from numpy.lib.arraypad import _validate_lengths

ImportError: cannot import name '_validate_lengths'

Нужна подсказка, чтобы решить эту ошибку. Спасибо.

import tensorflow as tf
from skimage import transform
from skimage import data
import matplotlib.pyplot as plt
import os
import numpy as np
from skimage.color import rgb2gray
import random

#listdir: This method returns a list containing the names of the entries in the directory given by path.
# Return True if path is an existing directory

def load_data(data_dir):
    # Get all subdirectories of data_dir. Each represents a label.
    directories = [d for d in os.listdir(data_dir)
                   if os.path.isdir(os.path.join(data_dir, d))]
    # Loop through the label directories and collect the data in
    # two lists, labels and images.
    labels = []
    images = []
    for d in directories:
        label_dir = os.path.join(data_dir, d)
        file_names = [os.path.join(label_dir, f)
                      for f in os.listdir(label_dir)
                      if f.endswith(".ppm")]
        for f in file_names:
            images.append(data.imread(f))
            labels.append(int(d))
    return images, labels


ROOT_PATH = "/home/tahir/PhD Study/Traffic Signs Using Tensorflow/"
train_data_dir = os.path.join(ROOT_PATH, "TrafficSigns/Training")
test_data_dir = os.path.join(ROOT_PATH, "TrafficSigns/Testing")

images, labels = load_data(train_data_dir)

# Print the `images` dimensions
print(images.ndim)

# Print the number of `images`'s elements
print(images.size)

# Print the first instance of `images`
images[0]