At Tim Peters' recommendation, add a dummy flush() method to PseudoFile.

Tools/idle/PyShell.py

@@ -593,6 +593,9 @@ class PseudoFile:
     def writelines(self, l):
         map(self.write, l)
 
+    def flush(self):
+        pass
+
 
 def main():
     debug = 0

Tools/idle/ScriptBinding.py

@@ -70,6 +70,9 @@ class PseudoFile:
     def writelines(self, l):
         map(self.write, l)
 
+    def flush(self):
+        pass
+
 
 class ScriptBinding: