remove redundant invocation of json doctests
diff --git a/Lib/test/test_json.py b/Lib/test/test_json.py
index 17ccdee..7b8f3de 100644
--- a/Lib/test/test_json.py
+++ b/Lib/test/test_json.py
@@ -11,7 +11,6 @@
 
 def test_main():
     test.test_support.run_unittest(json.tests.test_suite())
-    test.test_support.run_doctest(json)
 
 
 if __name__ == "__main__":