[core][tests][debugger] Remove nose

IPython/core/tests/test_debugger.py

@@ -18,8 +18,6 b' from tempfile import NamedTemporaryFile'
 from textwrap import dedent
 from unittest.mock import patch
 
-import nose.tools as nt
-
 from IPython.core import debugger
 from IPython.testing import IPYTHON_TESTING_TIMEOUT_SCALE
 from IPython.testing.decorators import skip_win32
@@ -66,13 +64,13 b' def test_longer_repr():'
     a = '1234567890'* 7
     ar = "'1234567890123456789012345678901234567890123456789012345678901234567890'"
     a_trunc = "'123456789012...8901234567890'"
-    nt.assert_equal(trepr(a), a_trunc)
+    assert trepr(a) == a_trunc
     # The creation of our tracer modifies the repr module's repr function
     # in-place, since that global is used directly by the stdlib's pdb module.
     with warnings.catch_warnings():
         warnings.simplefilter('ignore', DeprecationWarning)
         debugger.Tracer()
-    nt.assert_equal(trepr(a), ar)
+    assert trepr(a) == ar
 
 def test_ipdb_magics():
     '''Test calling some IPython magics from ipdb.