class_docstr: A backend that stores the chain in an HDF5 file using h5py
  
  .. note:: You must install `h5py <http://www.h5py.org/>`_ to use this
      backend.
  
  Args:
      filename (str): The name of the HDF5 file where the chain will be
          saved.
      name (str; optional): The name of the group where the chain will
          be saved.
      read_only (bool; optional): If ``True``, the backend will throw a
          ``RuntimeError`` if the file is opened with write access.
class_docstr_tok: ["A","backend","that","stores","the","chain","in","an","HDF5","file","using","h5py","..","note",":",":","You","must","install","`","h5py","<","http",":","\/\/www.h5py.org\/",">","`","_","to","use","this","backend",".","Args",":","filename","(","str",")",":","The","name","of","the","HDF5","file","where","the","chain","will","be","saved",".","name","(","str",";","optional",")",":","The","name","of","the","group","where","the","chain","will","be","saved",".","read_only","(","bool",";","optional",")",":","If","``","True","``",",","the","backend","will","throw","a","``","RuntimeError","``","if","the","file","is","opened","with","write","access","."]
code: def accepted(self):
      with self.open() as f:
          return f[self.name]["accepted"][...]
  
imports: from __future__ import division, print_function
  import os
  from tempfile import NamedTemporaryFile
  import numpy
  from ..None import __version__
  from .backend import Backend
label_desc: Use image node_id 9 for calling the HDFBackend obj's underlying member method code with example usage: obj.accepted() and returns: f