code: def expected_latest(self, column, slice_):
      loader = self.engine.get_loader(column)
  
      index = self.calendar[slice_]
      columns = self.assets
      values = loader.values(column.dtype, self.calendar, self.sids)[
          slice_
      ]
  
      if column.dtype.kind in ("O", "S", "U"):
          # For string columns, we expect a categorical in the output.
          return LabelArray(
              values,
              missing_value=column.missing_value,
          ).as_categorical_frame(
              index=index,
              columns=columns,
          )
  
      return DataFrame(
          loader.values(column.dtype, self.calendar, self.sids)[slice_],
          index=self.calendar[slice_],
          columns=self.assets,
      )
  
file_path: catalyst/tests/pipeline/test_column.py
imports: from contextlib2 import ExitStack
  from unittest import TestCase
  from pandas import date_range, DataFrame
  from pandas.util.testing import assert_frame_equal
  from catalyst.lib.labelarray import LabelArray
  from catalyst.pipeline import Pipeline
  from catalyst.pipeline.data.testing import TestingDataSet
  from catalyst.testing import chrange, temp_pipeline_engine
  from catalyst.utils.pandas_utils import ignore_pandas_nan_categorical_warning
label_desc: Use image node_id 3 for calling the LatestTestCase obj's underlying member method code with example usage: obj.expected_latest(column, slice_) and returns: DataFrame, LabelArray