class_docstr: Parameters
  ---------
  country_group : h5py.Group
      The group for a single country in an HDF5 daily pricing file.
class_docstr_tok: ["Parameters","--","--","--","--","-","country_group",":","h5py.Group","The","group","for","a","single","country","in","an","HDF5","daily","pricing","file","."]
docstr: Returns
  -------
  sessions : DatetimeIndex
     All session labels (unioning the range for all assets) which the
     reader can provide.
docstr_tok: ["Returns","--","--","--","-","sessions",":","DatetimeIndex","All","session","labels","(","unioning","the","range","for","all","assets",")","which","the","reader","can","provide","."]
code: def sessions(self):
      """
      Returns
      -------
      sessions : DatetimeIndex
         All session labels (unioning the range for all assets) which the
         reader can provide.
      """
      return pd.to_datetime(self.dates, utc=True)
  
imports: from functools import partial
  import h5py
  import logbook
  import numpy
  import pandas
  from six import iteritems, raise_from, viewkeys
  from six.moves import reduce
  from zipline.data.bar_reader import NoDataAfterDate, NoDataBeforeDate, NoDataForSid, NoDataOnDate
  from zipline.data.session_bars import CurrencyAwareSessionBarReader
  from zipline.utils.memoize import lazyval
  from zipline.utils.numpy_utils import bytes_array_to_native_str_object_array
  from zipline.utils.pandas_utils import check_indexes_all_same
label_desc: Use image node_id 19 for calling the HDF5DailyBarReader obj's underlying member method code with example usage: obj.sessions() and returns: pd