code: def construct_mapping(self, node, deep=False):
      
  
      mapping = ODict()
  
      for key_node, value_node in node.value:
          key = self.construct_object(key_node, deep=deep)
          value = self.construct_object(value_node, deep=deep)
  
          mapping[key] = value
  
      return mapping
docs: Use ODict for maps