python使用字节处理文件

>>> with open(`dog_breeds.txt`, 'rb') as reader:

>>>     print(reader.readline())

b'Pug\n'

>>> with open('jack_russell.png', 'rb') as byte_reader:

>>>     print(byte_reader.read(1))

>>>     print(byte_reader.read(3))

>>>     print(byte_reader.read(2))

>>>     print(byte_reader.read(1))

>>>     print(byte_reader.read(1))

b'\x89'

b'PNG'

b'\r\n'

b'\x1a'

b'\n'