use capsys.readouterr() as named tuple (#24489)

Author: simonjayhawkins

pandas/tests/series/test_duplicates.py

@@ -76,12 +76,12 @@ def __init__(self, val):
         def __ne__(self, other):
             raise Exception("NEQ not supported")
 
-    li = [Foo(i) for i in range(5)]
-    s = Series(li, index=[i for i in range(5)])
-    _, err = capsys.readouterr()
+    with capsys.disabled():
+        li = [Foo(i) for i in range(5)]
+        s = Series(li, index=[i for i in range(5)])
     s.is_unique
-    _, err = capsys.readouterr()
-    assert len(err) == 0
+    captured = capsys.readouterr()
+    assert len(captured.err) == 0
 
 
 @pytest.mark.parametrize(