Issue #23865: close() methods in multiple modules now are idempotent and more
robust at shutdown. If needs to release multiple resources, they are released
even if errors are occured.
diff --git a/Lib/xml/sax/expatreader.py b/Lib/xml/sax/expatreader.py
index 9de3e72..cd243e6 100644
--- a/Lib/xml/sax/expatreader.py
+++ b/Lib/xml/sax/expatreader.py
@@ -214,14 +214,16 @@
             self._err_handler.fatalError(exc)
 
     def close(self):
-        if self._entity_stack:
+        if self._entity_stack or self._parser is None:
             # If we are completing an external entity, do nothing here
             return
-        self.feed("", isFinal = 1)
-        self._cont_handler.endDocument()
-        self._parsing = 0
-        # break cycle created by expat handlers pointing to our methods
-        self._parser = None
+        try:
+            self.feed("", isFinal = 1)
+            self._cont_handler.endDocument()
+        finally:
+            self._parsing = 0
+            # break cycle created by expat handlers pointing to our methods
+            self._parser = None
 
     def _reset_cont_handler(self):
         self._parser.ProcessingInstructionHandler = \