在为pandas DataFrame编写好的元数据处理程序几个小时之后，突然间：
>>> import pandas as pd
>>> a = pd.DataFrame({'frame':[0,1,2,3,4,5,6,7], 'x':[1,2,2,2,3,4,2,11], 'y':[2,2,3,2,2,3,2,10]})
>>> a
frame x y
0 0 1 2
1 1 2 2
2 2 2 3
3 3 2 2
4 4 3 2
5 5 4 3
6 6 2 2
7 7 11 10
>>> a.set_index('frame')
x y
frame
0 1 2
1 2 2
2 2 3
3 2 2
4 3 2
5 4 3
6 2 2
7 11 10
>>> type(a._metadata)
list
>>> a._metadata.append(dict())
>>> a.set_index('frame')
---------------------------------------------------------------------------
TypeError Traceback (most recent call last)
<ipython-input-11-a271477b5f41> in <module>()
----> 1 a.set_index('frame')
/usr/lib/python2.7/dist-packages/pandas/core/frame.pyc in set_index(self, keys, drop, append, inplace, verify_integrity)
2453 frame = self
2454 else:
-> 2455 frame = self.copy()
2456
2457 arrays = []
/usr/lib/python2.7/dist-packages/pandas/core/generic.pyc in copy(self, deep)
2212 """
2213 data = self._data.copy(deep=deep)
-> 2214 return self._constructor(data).__finalize__(self)
2215
2216 def convert_objects(self, convert_dates=True, convert_numeric=False,
/usr/lib/python2.7/dist-packages/pandas/core/generic.pyc in __finalize__(self, other, method, **kwargs)
1923 if isinstance(other, NDFrame):
1924 for name in self._metadata:
-> 1925 object.__setattr__(self, name, getattr(other, name, None))
1926 return self
1927
TypeError: getattr(): attribute name must be string
附加字典可能不是最终方式，我已将其更改为
>>> a._metadata = dict()
但是，这应该不是，或者是吗？这是一个错误还是我的错误？
谢谢，Kami