code: def test_cross_below(self):
      result = self.utils.cross(
          self.crosseddf["b"], self.crosseddf["a"], above=False
      )
      self.assertIsInstance(result, Series)
      npt.assert_array_equal(result, self.crosseddf["crossed"])
  
imports: from .config import sample_data
  from .context import pandas_ta
  from unittest import skip, TestCase
  from unittest.mock import patch
  import numpy
  import numpy.testing
  from pandas import DataFrame, Series
  from pandas.api.types import is_datetime64_ns_dtype, is_datetime64tz_dtype
label_desc: Use image node_id 13 for calling the TestUtilities obj's underlying member method code with example usage: obj.test_cross_below() without return types