robie@xps:~$ python3
Python 3.5.3 (default, Jan 19 2017, 14:11:04) 
[GCC 6.3.0 20170118] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> 'foo'.split('\n')
['foo']
>>> b'foo'.split('\n')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: a bytes-like object is required, not 'str'
>>> 
robie@xps:~$ python2
Python 2.7.13 (default, Jan 19 2017, 14:48:08) 
[GCC 6.3.0 20170118] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> 'foo'.split('\n')
['foo']
>>> b'foo'.split('\n')
['foo']
>>>