cleaner string/bytes solution, closes #4759

Thanks @takluyver for the suggestion. I'll eventually learn this
strings/bytes/unicode stuff properly for Python3.

IPython/terminal/tests/test_embed.py

@@ -1,54 +1,54 b''
 """Test embedding of IPython"""
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2013 The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 import sys
 import nose.tools as nt
 from IPython.utils.process import process_handler
 from IPython.utils.tempdir import NamedFileInTemporaryDirectory
 
 #-----------------------------------------------------------------------------
 # Tests
 #-----------------------------------------------------------------------------
 
-_sample_embed = """
+_sample_embed = b"""
 from __future__ import print_function
 import IPython
 
 a = 3
 b = 14
 print(a, '.', b)
 
 IPython.embed()
 
 print('bye!')
 """
 
-_exit = "exit\r".encode('UTF-8')
+_exit = b"exit\r"
 
 def test_ipython_embed():
     """test that `IPython.embed()` works"""
     with NamedFileInTemporaryDirectory('file_with_embed.py') as f:
-        f.write(_sample_embed.encode('UTF-8'))
+        f.write(_sample_embed)
         f.flush()
 
         # run `python file_with_embed.py`
         cmd = [sys.executable, f.name]
 
         _, out, p = process_handler(cmd,
                 lambda p: (p.stdin.write(_exit), p.communicate()[:], p))
         std = out[0].decode('UTF-8')
         nt.assert_equal(p.returncode, 0)
         nt.assert_in('3 . 14', std)
         nt.assert_in('IPython', std)
         nt.assert_in('bye!', std)