def symbolize_key(key)
      return key unless key.respond_to?(:split)
      key.split(':').last.underscore.to_sym
    end
def symbolize_key(key)
      return key unless key.respond_to?(:split)
      key.split(':').last.underscore.to_sym
    end
Given a key, convert to symbol, removing XML namespace, if any.
 @param [String] key - a key, either "abc" or "abc:def"
 @return [Symbol]