'Get a Panel that is the current data in view. It is not safe to persist
these objects because internal data might change'

def get_current(self):

    where = slice(self._oldest_frame_idx(), self._pos)
    major_axis = pd.DatetimeIndex(deepcopy(self.date_buf[where]), tz='utc')
    return pd.Panel(self.buffer.values[:, where, :], self.items, major_axis, self.minor_axis, dtype=self.dtype)
