code: def df():
      mock_data = {
          "userID": [1, 2, 3, 4, 5, 6, 7, 8, 9, 10],
          "itemID": [1, 2, 3, 4, 5, 6, 7, 8, 9, 10],
          "rating": [2.0, 4.0, 1.0, 4.0, 1.0, 2.0, 5.0, 1.0, 1.0, 2.0],
          "genre": [
              "Action|Comedy",
              "Drama",
              "Drama|Romance|War",
              "Drama|Sci-Fi",
              "Horror",
              "Action|Horror|Sci-Fi|Thriller",
              "Drama|Romance|War",
              "Western",
              "Comedy",
              "Horror",
          ],
          "occupation": [
              "engineer",
              "student",
              "retired",
              "administrator",
              "writer",
              "administrator",
              "student",
              "executive",
              "student",
              "other",
          ],
      }
      return pd.DataFrame(mock_data)
  
file_path: recommenders/tests/unit/recommenders/models/test_lightfm_utils.py
imports: import pytest
  import itertools
  import numpy
  import pandas
  from lightfm.data import Dataset
  from lightfm import LightFM, cross_validation
  from recommenders.models.lightfm.lightfm_utils import track_model_metrics, similar_users, similar_items
label_desc: Use image node_id 1 for calling a global function with example usage: df() and returns: pd