import numpy as np
import gzip
import struct


def load_images(filename):
    # Open and unzip the file of images :
    with gzip.open(filename, 'rb') as f:
        # read the header, information into a bunch of variables:
        _ignored, n_images, image_columns, image_rows = struct.unpack('>IIII', bytearray(f.read()[:16]))
        print(_ignored, n_images, image_columns, image_rows)
        print(f.read()[:16])
        # read all the pixels into a long numpy array :
        all_pixels = np.frombuffer(f.read(), dtype=np.uint8)
        print(all_pixels)
        print(all_pixels.shape)
        print(all_pixels.ndim)
        # reshape the array into a matrix where each line is an image:
        images_matrix = all_pixels.reshape(n_images, image_columns * image_rows)

Error:
load_images("\\MNIST\\train-images-idx3-ubyte.gz")
2051 60000 28 28
b''
[]
(0,)
1
Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "<input>", line 19, in load_images
ValueError: cannot reshape array of size 0 into shape (60000,784)

file.seek(16)