title: Check if HDF5 Store object is empty?
body: <p>I am using pandas HDFSTore object to open a hdf5 file and store <code>DataFrame</code> objects. But before I do that, I want to find out if the file is empty. Is there a way to find out if my</p>
  
  <pre><code>In[12]:
  import pandas
  store = pandas.io.pytables.HDFStore('store.h5')
  Out[12]:
  &lt;class 'pandas.io.pytables.HDFStore'&gt;
  File path: store.h5
  Empty
  </code></pre>
  
  <p>Is there a way to get a browse the hierarchy tree in store.h5 to check if the object is empty. I would like to get a list of objects in store.h5</p>