code: def test_baseline(self):
      data = arange(100).reshape(self.ndates, self.nsids)
      baseline = DataFrame(data, index=self.dates, columns=self.sids)
      loader = DataFrameLoader(USEquityPricing.close, baseline)
  
      dates_slice = slice(None, 10, None)
      sids_slice = slice(1, 3, None)
      [adj_array] = loader.load_adjusted_array(
          US_EQUITIES,
          [USEquityPricing.close],
          self.dates[dates_slice],
          self.sids[sids_slice],
          self.mask[dates_slice, sids_slice],
      ).values()
  
      for idx, window in enumerate(adj_array.traverse(window_length=3)):
          expected = baseline.values[dates_slice, sids_slice][
              idx : idx + 3
          ]
          assert_array_equal(window, expected)
  
file_path: zipline/tests/pipeline/test_frameload.py
imports: from unittest import TestCase
  from mock import patch
  from numpy import arange, ones
  from numpy.testing import assert_array_equal
  from pandas import DataFrame, DatetimeIndex, Int64Index
  from trading_calendars import get_calendar
  from zipline.lib.adjustment import ADD, Float64Add, Float64Multiply, Float64Overwrite, MULTIPLY, OVERWRITE
  from zipline.pipeline.data import USEquityPricing
  from zipline.pipeline.domain import US_EQUITIES
  from zipline.pipeline.loaders.frame import DataFrameLoader
label_desc: Use image node_id 4 for calling the DataFrameLoaderTestCase obj's underlying member method code with example usage: obj.test_baseline() without return types