解决UnicodeDecodeError: 'ascii' codec can't decode byte 0x8b in position 6: ordinal not in range(128)

关于利用pickle.load(）载入文件出现如下错误的解决办法。

UnicodeDecodeError                        Traceback (most recent call last)
input-16-9506c06e646a> in <module>()
      1 # Load the raw CIFAR-10 data.
      2 cifar10_dir = 'cs231n/datasets/cifar-10-batches-py'
----> 3 X_train, y_train, X_test, y_test = load_CIFAR10(cifar10_dir)
      4 
      5 # As a sanity check, we print out the size of the training and test data.

D:\python3wp\assignment1\cs231n\data_utils.py in load_CIFAR10(ROOT)
     20   for b in range(1,6):
     21     f = os.path.join(ROOT, 'data_batch_%d' % (b, ))
---> 22     X, Y = load_CIFAR_batch(f)
     23     xs.append(X)
     24     ys.append(Y)

D:\python3wp\assignment1\cs231n\data_utils.py in load_CIFAR_batch(filename)
      7   """ load single batch of cifar """
      8   with open(filename, 'rb') as f:
----> 9     datadict = pickle.load(f)
     10     X = datadict['data']
     11     Y = datadict['labels']

UnicodeDecodeError: 'ascii' codec can't decode byte 0x8b in position 6: ordinal not in range(128)

首先给出pickle.load()的函数解释：
pickle.load()
pickle.load(file, *, fix_imports=True, encoding=”ASCII”, errors=”strict”)
Read a pickled object representation from the open file object file and return the reconstituted object hierarchy specified therein. This is equivalent to Unpickler(file).load().
The protocol version of the pickle is detected automatically, so no protocol argument is needed. Bytes past the pickled object’s representation are ignored.
The argument file must have two methods, a read() method that takes an integer argument, and a readline() method that requires no arguments. Both methods should return bytes. Thus file can be an on-disk file opened for binary reading, an io.BytesIO object, or any other custom object that meets this interface.
Optional keyword arguments are fix_imports, encoding and errors, which are used to control compatibility support for pickle stream generated by Python 2. If fix_imports is true, pickle will try to map the old Python 2 names to the new names used in Python 3. The encoding and errors tell pickle how to decode 8-bit string instances pickled by Python 2; these default to ‘ASCII’ and ‘strict’, respectively. The encoding can be ‘bytes’ to read these 8-bit string instances as bytes objects.

import pickle
li = [1, 2, 3]
pickle.dump(li, open('db', 'wb'))
ret = pickle.load(open('db', 'rb'))
print(ret)

也就是说pickle.load()默认解码是以encoding=”ASCII”解码的,而我们要载入的文件并不是以”ASCII”形式存储的，所以要改变参数encoding=” ”
解决方式如下：

pickle.load(f,encoding='bytes')

这样编码可以用“字节”来读取这些8位字符串实例作为字节对象。