code: def test_frame_apply(self):
      pdf, psdf = self.df_pair
  
      self.assert_eq(
          psdf.apply(lambda x: x).sort_index(),
          pdf.apply(lambda x: x).sort_index(),
      )
      self.assert_eq(
          psdf.apply(lambda x: x, axis=1).sort_index(),
          pdf.apply(lambda x: x, axis=1).sort_index(),
      )
  
imports: import numpy
  import pandas
  from pandas.api.types import CategoricalDtype
  import pyspark.pandas
  from pyspark.testing.pandasutils import ComparisonTestBase, TestUtils
label_desc: Use image node_id 13 for calling the CategoricalTestsMixin obj's underlying member method code with example usage: obj.test_frame_apply() without return types