bpo-37685: Use singletons ALWAYS_EQ and NEVER_EQ in more tests. (GH-15167)

diff --git a/Lib/test/test_collections.py b/Lib/test/test_collections.py
index 0119c77..7f01de6 100644
--- a/Lib/test/test_collections.py
+++ b/Lib/test/test_collections.py
@@ -1472,9 +1472,6 @@
 
     def test_issue26915(self):
         # Container membership test should check identity first
-        class CustomEqualObject:
-            def __eq__(self, other):
-                return False
         class CustomSequence(Sequence):
             def __init__(self, seq):
                 self._seq = seq
@@ -1484,7 +1481,7 @@
                 return len(self._seq)
 
         nan = float('nan')
-        obj = CustomEqualObject()
+        obj = support.NEVER_EQ
         seq = CustomSequence([nan, obj, nan])
         containers = [
             seq,