code: def df():
      """fixture for groupby_topk"""
      return pd.DataFrame(
          [
              {
                  "age": 22,
                  "major": "science",
                  "ID": 145,
                  "result": "pass",
              },
              {
                  "age": 20,
                  "major": "history",
                  "ID": 322,
                  "result": "fail",
              },
              {
                  "age": 23,
                  "major": "history",
                  "ID": 321,
                  "result": "pass",
              },
              {"age": 21, "major": "law", "ID": 49, "result": "fail"},
              {
                  "age": 19,
                  "major": "mathematics",
                  "ID": 224,
                  "result": "pass",
              },
              {
                  "age": 20,
                  "major": "science",
                  "ID": 132,
                  "result": "pass",
              },
          ]
      )
  
file_path: pyjanitor/tests/functions/test_groupby_topk.py
imports: import pandas
  import pytest
  from pandas.testing import assert_frame_equal
label_desc: Use image node_id 1 for calling a global function with example usage: df() and returns: pd