diff -r 3a57eafd8401 Lib/configparser.py
--- a/Lib/configparser.py	Tue May 24 09:15:14 2016 +0300
+++ b/Lib/configparser.py	Tue May 24 22:03:08 2016 +0200
@@ -147,10 +147,11 @@
 import sys
 import warnings
 
-__all__ = ["NoSectionError", "DuplicateOptionError", "DuplicateSectionError",
-           "NoOptionError", "InterpolationError", "InterpolationDepthError",
-           "InterpolationMissingOptionError", "InterpolationSyntaxError",
-           "ParsingError", "MissingSectionHeaderError",
+__all__ = ["Error", "NoSectionError", "DuplicateOptionError",
+           "DuplicateSectionError", "NoOptionError", "InterpolationError",
+           "InterpolationDepthError", "InterpolationMissingOptionError",
+           "InterpolationSyntaxError", "ParsingError",
+           "MissingSectionHeaderError",
            "ConfigParser", "SafeConfigParser", "RawConfigParser",
            "Interpolation", "BasicInterpolation",  "ExtendedInterpolation",
            "LegacyInterpolation", "SectionProxy", "ConverterMapping",
diff -r 3a57eafd8401 Lib/test/test_configparser.py
--- a/Lib/test/test_configparser.py	Tue May 24 09:15:14 2016 +0300
+++ b/Lib/test/test_configparser.py	Tue May 24 22:03:08 2016 +0200
@@ -2052,5 +2052,10 @@
             self.assertEqual(cfg['two'].getlen('one'), 5)
 
 
+class MiscTestCase(unittest.TestCase):
+    def test__all__(self):
+        support.check__all__(self, configparser)
+
+
 if __name__ == '__main__':
     unittest.main()