什么是python中的'FrameFixed'对象？

Question

import numpy as np
import pandas as pd
df = pd.DataFrame(np.random.randn(50,4), columns = list('ABCD'))
with pd.HDFStore("test.h5") as store:
    store['df'] = df
with pd.HDFStore("test.h5") as store:
    print store.select_as_coordinates('df')

这给了我一个属性错误

----> 3     print store.select_as_coordinates(keys[1])
C:\...\Continuum\Anaconda2\lib\sitepackages\pandas\io\pytables.pyc in select_as_coordinates(self, key, where, start, stop, **kwargs)
    755         """
    756         where = _ensure_term(where, scope_level=1)
--> 757         return self.get_storer(key).read_coordinates(where=where, start=start,
    758                                                      stop=stop, **kwargs)
    759 

AttributeError: 'FrameFixed' object has no attribute 'read_coordinates'

我尝试在python中查找FrameFixed个对象，但没有成功。任何帮助将不胜感激。