Fix a typo, unfortunately propagated by word-completion.

pep-0280.txt

@@ -261,7 +261,7 @@ Additional Ideas
         class cell(object):
             def __init__(self, obj=NULL, builtin=0):
                 self.objptr = obj
-                self.buitinflag = builtin
+                self.builtinflag = builtin
 
     and a celldict maps strings to this version of cells.  builtinflag
     is true when and only when objptr contains a value obtained from
@@ -305,26 +305,26 @@ Additional Ideas
                 if key in self.basedict:
                     c.objptr = self.basedict[key]
                     assert c.objptr is not NULL # else "in" lied
-                    c.buitinflag = 1
+                    c.builtinflag = 1
                 else:
                     # There is no builtin with the same name.
-                    assert not c.buitinflag
+                    assert not c.builtinflag
 
             def keys(self):
                 return [k for k, c in self.__dict.iteritems()
-                        if c.objptr is not NULL and not c.buitinflag]
+                        if c.objptr is not NULL and not c.builtinflag]
 
             def items(self):
                 return [k, c.objptr for k, c in self.__dict.iteritems()
-                        if c.objptr is not NULL and not c.buitinflag]
+                        if c.objptr is not NULL and not c.builtinflag]
 
             def values(self):
                 preturn [c.objptr for c in self.__dict.itervalues()
-                        if c.objptr is not NULL and not c.buitinflag]
+                        if c.objptr is not NULL and not c.builtinflag]
 
             def clear(self):
                 for c in self.__dict.values():
-                    if not c.buitinflag:
+                    if not c.builtinflag:
                         c.objptr = NULL
 
             # Etc.
@@ -357,14 +357,14 @@ Additional Ideas
         def reflect_bltin_del(self, key):
             c = self.__dict.get(key)
             assert c is not None # else we were already out of synch
-            if c.buitinflag:
+            if c.builtinflag:
                 # Put us back in synch.
                 c.objptr = NULL
-                c.buitinflag = 0
+                c.builtinflag = 0
             # Else we're shadowing the builtin, so don't care that
             # the builtin went away.
 
-    Note that c.buitinflag protects from us erroneously deleting a
+    Note that c.builtinflag protects from us erroneously deleting a
     module global of the same name.  Adding a new (key, value) builtin
     pair is similar:
 
@@ -378,10 +378,10 @@ Additional Ideas
                 # but doesn't anymore; rehabilitate it.
                 assert not c.builtinflag
                 c.objptr = value
-                c.buitinflag = 1
+                c.builtinflag = 1
             else:
                 # We're shadowing it already.
-                assert not c.buitinflag
+                assert not c.builtinflag
 
     Changing the value of an existing builtin can be viewed as deleting
     the name, then adding it again.  Indeed, since mutating builtins is