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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _gettables(self):
 """Return a list of hdf5 tables name PyMCsamples. """


        groups = self._h5file.list_nodes("/")
        if len(groups) == 0:
            return []
        else:
            return [
                gr.PyMCsamples for gr in groups if gr._v_name[:5] == 'chain']