diff -ur astropy-3.1.1/astropy/config/configuration.py astropy-3.1.1.configobj/astropy/config/configuration.py
--- astropy-3.1.1/astropy/config/configuration.py	2019-01-01 00:54:51.000000000 +0100
+++ astropy-3.1.1.configobj/astropy/config/configuration.py	2019-02-17 18:48:51.688306288 +0100
@@ -16,7 +16,7 @@
 import re
 from warnings import warn
 
-from astropy.extern.configobj import configobj, validate
+import configobj, validate
 from astropy.utils.exceptions import AstropyWarning, AstropyDeprecationWarning
 from astropy.utils import find_current_module
 from astropy.utils.introspection import resolve_name