[utils][tests][io] Remove nose

IPython/utils/tests/test_io.py

@@ -11,8 +11,6 b' from io import StringIO'
 from subprocess import Popen, PIPE
 import unittest
 
-import nose.tools as nt
-
 from IPython.utils.io import IOStream, Tee, capture_output
 
 
@@ -22,7 +20,7 b' def test_tee_simple():'
     text = 'Hello'
     tee = Tee(chan, channel='stdout')
     print(text, file=chan)
-    nt.assert_equal(chan.getvalue(), text+"\n")
+    assert chan.getvalue() == text + "\n"
 
 
 class TeeTestCase(unittest.TestCase):
@@ -39,7 +37,7 b' class TeeTestCase(unittest.TestCase):'
 
         print(text, end='', file=chan)
         trap_val = trap.getvalue()
-        nt.assert_equal(chan.getvalue(), text)
+        self.assertEqual(chan.getvalue(), text)
 
         tee.close()
 
@@ -82,8 +80,8 b' class TestIOStream(unittest.TestCase):'
         """capture_output() context works"""
         
         with capture_output() as io:
-            print('hi, stdout')
-            print('hi, stderr', file=sys.stderr)
+            print("hi, stdout")
+            print("hi, stderr", file=sys.stderr)
         
-        nt.assert_equal(io.stdout, 'hi, stdout\n')
-        nt.assert_equal(io.stderr, 'hi, stderr\n')
+        self.assertEqual(io.stdout, "hi, stdout\n")
+        self.assertEqual(io.stderr, "hi, stderr\n")