code: def kv(d):
          
          return ((key, value) for key, value in iteritems(d) if key != _meta)
docs: Equivalent to dict.items().
          
          Usage::
          
              >>> for key, node in DictTree.kv(d):
              >>>     print(key, DictTree.getattr(node, "population"))  
              MD 200000
              VA 100000