MAINT: Remove testing.assert_isinstance (#15652)

Deprecated in 0.17.0 xref gh-10458

Author: gfyoung

pandas/tests/test_testing.py

@@ -765,9 +765,6 @@ def test_warning(self):
  with tm.assert_produces_warning(FutureWarning, check_stacklevel=False):
  self.assertNotAlmostEquals(1, 2)
 
- with tm.assert_produces_warning(FutureWarning, check_stacklevel=False):
- tm.assert_isinstance(Series([1, 2]), Series, msg='xxx')
-
 
 class TestLocale(tm.TestCase):
 

pandas/util/testing.py

@@ -991,11 +991,6 @@ def assertIsInstance(obj, cls, msg=''):
  raise AssertionError(err_msg.format(msg, cls, type(obj)))
 
 
-def assert_isinstance(obj, class_type_or_tuple, msg=''):
- return deprecate('assert_isinstance', assertIsInstance)(
- obj, class_type_or_tuple, msg=msg)
-
-
 def assertNotIsInstance(obj, cls, msg=''):
  """Test that obj is not an instance of cls
  (which can be a class or a tuple of classes,