KeyError:'_ OrderedDict__root？

Question

嗨,我有以下代码片段,它给出了KeyError.我已经检查了其他链接,指明make __init__ call to Ordered Dict我做了什么.但仍然没有运气.

from collections import OrderedDict

class BaseExcelNode(OrderedDict):
    def __init__(self):
        super(BaseExcelNode, self).__init__()
        self.start_row = -1
        self.end_row = -1
        self.col_no = -1

    def __getattr__(self, name):
        return self[name]

    def __setattr__(self, name, value):
        self[name] = value
BaseExcelNode()

Error:

Traceback (most recent call last):
  File "CIMParser.py", line 29, in <module>
    BaseExcelNode()
  File "CIMParser.py", line 9, in __init__
    super(BaseExcelNode, self).__init__()
  File "C:\Python27\lib\collections.py", line 64, in __init__
    self.__root
  File "CIMParser.py", line 15, in __getattr__
    return self[name]
KeyError: '_OrderedDict__root'

Answer 1

使用猴子补丁方法：

from collections import OrderedDict

class BaseExcelNode(OrderedDict):
    def __init__(self):
        super(BaseExcelNode, self).__init__()
        self.start_row = -1
        self.end_row = -1
        self.col_no = -1

    def __getattr__(self, name):
        if not name.startswith('_'):
            return self[name]
        super(BaseExcelNode, self).__getattr__(name)

    def __setattr__(self, name, value):
        if not name.startswith('_'):
            self[name] = value
        else:
            super(BaseExcelNode, self).__setattr__(name, value)

b = BaseExcelNode()