Add is_declared_global() which distinguishes between implicit and

explicit global variables.

Lib/symtable.py

@@ -190,6 +190,9 @@ class Symbol(object):
     def is_global(self):
         return bool(self.__scope in (GLOBAL_IMPLICIT, GLOBAL_EXPLICIT))
 
+    def is_declared_global(self):
+        return bool(self.__scope == GLOBAL_EXPLICIT)
+
     def is_local(self):
         return bool(self.__flags & DEF_BOUND)
 

Lib/test/test_symtable.py

@@ -98,7 +98,9 @@ class SymtableTest(unittest.TestCase):
 
     def test_globals(self):
         self.assertTrue(self.spam.lookup("glob").is_global())
+        self.assertFalse(self.spam.lookup("glob").is_declared_global())
         self.assertTrue(self.spam.lookup("bar").is_global())
+        self.assertTrue(self.spam.lookup("bar").is_declared_global())
         self.assertFalse(self.internal.lookup("x").is_global())
         self.assertFalse(self.Mine.lookup("instance_var").is_global())