flesh out __all__

remove debugging code in if __debug__:

add get_children() method on SymbolTable
diff --git a/Lib/symtable.py b/Lib/symtable.py
index 3133633..6401d51 100644
--- a/Lib/symtable.py
+++ b/Lib/symtable.py
@@ -8,7 +8,8 @@
 
 import weakref
 
-__all__ = ["symtable", "SymbolTable", "newSymbolTable"]
+__all__ = ["symtable", "SymbolTable", "newSymbolTable", "Class",
+           "Function", "Symbol"]
 
 def symtable(code, filename, compile_type):
     raw = _symtable.symtable(code, filename, compile_type)
@@ -117,6 +118,10 @@
                 for st in self._table.children
                 if st.name == name]
 
+    def get_children(self):
+        return [newSymbolTable(st, self._filename)
+                for st in self._table.children]
+
 class Function(SymbolTable):
 
     # Default values for instance variables
@@ -236,19 +241,6 @@
             raise ValueError, "name is bound to multiple namespaces"
         return self.__namespaces[0]
 
-if __debug__:
-    class Foo:
-        version = 1
-
-    class Foo:
-        version = 2
-
-    class Foo:
-        version = 3
-
-    def execfunc(x):
-        exec x in y
-    
 if __name__ == "__main__":
     import os, sys
     src = open(sys.argv[0]).read()