Issue #808164: Fixed socket.close to avoid references to globals, to

avoid issues when socket.close is called from a __del__ method.

Lib/socket.py

@@ -172,10 +172,12 @@ class socket(_socket.socket):
         if self._closed:
             self.close()
 
-    def _real_close(self):
-        _socket.socket.close(self)
+    def _real_close(self, _ss=_socket.socket):
+        # This function should not reference any globals.  See Issue808164
+        _ss.close(self)
 
     def close(self):
+        # This function should not reference any globals.  See Issue808164
         self._closed = True
         if self._io_refs <= 0:
             self._real_close()

Misc/NEWS

@@ -142,6 +142,9 @@ Extensions
 Library
 -------
 
+- Issue #808164: Fixed socket.close to avoid references to globals, to
+  avoid issues when socket.close is called from a __del__ method.
+
 - Issue #9706: ssl module provides a better error handling in various 
   circumstances.