bpo-15999: Always pass bool instead of int to the expat parser. (GH-15622)

diff --git a/Lib/xml/sax/expatreader.py b/Lib/xml/sax/expatreader.py
index 5066ffc..e334ac9 100644
--- a/Lib/xml/sax/expatreader.py
+++ b/Lib/xml/sax/expatreader.py
@@ -93,7 +93,7 @@
         self._parser = None
         self._namespaces = namespaceHandling
         self._lex_handler_prop = None
-        self._parsing = 0
+        self._parsing = False
         self._entity_stack = []
         self._external_ges = 0
         self._interning = None
@@ -203,10 +203,10 @@
 
     # IncrementalParser methods
 
-    def feed(self, data, isFinal = 0):
+    def feed(self, data, isFinal=False):
         if not self._parsing:
             self.reset()
-            self._parsing = 1
+            self._parsing = True
             self._cont_handler.startDocument()
 
         try:
@@ -237,13 +237,13 @@
             # If we are completing an external entity, do nothing here
             return
         try:
-            self.feed("", isFinal = 1)
+            self.feed(b"", isFinal=True)
             self._cont_handler.endDocument()
-            self._parsing = 0
+            self._parsing = False
             # break cycle created by expat handlers pointing to our methods
             self._parser = None
         finally:
-            self._parsing = 0
+            self._parsing = False
             if self._parser is not None:
                 # Keep ErrorColumnNumber and ErrorLineNumber after closing.
                 parser = _ClosedParser()
@@ -307,7 +307,7 @@
         self._parser.SetParamEntityParsing(
             expat.XML_PARAM_ENTITY_PARSING_UNLESS_STANDALONE)
 
-        self._parsing = 0
+        self._parsing = False
         self._entity_stack = []
 
     # Locator methods