code: def df_multi():
      """MultiIndex dataframe fixture."""
      # https://stackoverflow.com/a/58328741/7175713
      tuples = list(
          zip(
              *[
                  [
                      "bar",
                      "bar",
                      "baz",
                      "baz",
                      "foo",
                      "foo",
                      "qux",
                      "qux",
                  ],
                  [1.0, 2.0, 1.0, 2.0, 1.0, 2.0, 1.0, 2.0],
              ]
          )
      )
  
      idx = pd.MultiIndex.from_tuples(tuples, names=["first", "second"])
      return pd.DataFrame(
          np.random.randn(8, 2), index=idx, columns=["A", "B"]
      )
  
file_path: pyjanitor/tests/functions/test_change_index_dtype.py
imports: import numpy
  import pandas
  import pytest
  from pandas.testing import assert_frame_equal
label_desc: Use image node_id 2 for calling a global function with example usage: df_multi() and returns: pd