code: def test_pivot_long_wide_long():
      """
      Test transformation from long to wide and back to long form.
      """
  
      df_in = pd.DataFrame(
          [
              {
                  "a": 1,
                  "b": 2,
                  "name": "ben",
                  "points": 22,
                  "marks": 5,
                  "sets": 13,
              },
              {
                  "a": 1,
                  "b": 2,
                  "name": "dave",
                  "points": 23,
                  "marks": 4,
                  "sets": 11,
              },
          ]
      )
  
      result = df_in.pivot_wider(
          index=["a", "b"],
          names_from="name",
          values_from=["points", "marks", "sets"],
          names_sep=None,
      )
  
      result = result.pivot_longer(
          index=["a", "b"],
          names_to=(".value", "name"),
          names_sep="_",
      )
      assert_frame_equal(result, df_in)
  
imports: import numpy
  import pandas
  import pytest
  from pandas.testing import assert_frame_equal
label_desc: Use image node_id 19 for calling a global function with example usage: test_pivot_long_wide_long() without return types