code: def days_and_sids_for_frames(frames):
      """
      Returns the date index and sid columns shared by a list of dataframes,
      ensuring they all match.
  
      Parameters
      ----------
      frames : list[pd.DataFrame]
          A list of dataframes indexed by day, with a column per sid.
  
      Returns
      -------
      days : np.array[datetime64[ns]]
          The days in these dataframes.
      sids : np.array[int64]
          The sids in these dataframes.
  
      Raises
      ------
      ValueError
          If the dataframes passed are not all indexed by the same days
          and sids.
      """
      if not frames:
          days = np.array([], dtype="datetime64[ns]")
          sids = np.array([], dtype="int64")
          return days, sids
  
      # Ensure the indices and columns all match.
      check_indexes_all_same(
          [frame.index for frame in frames],
          message="Frames have mismatched days.",
      )
      check_indexes_all_same(
          [frame.columns for frame in frames],
          message="Frames have mismatched sids.",
      )
  
      return frames[0].index.values, frames[0].columns.values
  
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 2 for calling a global function with example usage: days_and_sids_for_frames(frames) and returns: frames,  frames, days,  sids