code: def init_data():
      """
      Data used to test initialization method
      """
      data_dir = join(dirname(__file__), "data")
      data = pd.read_csv(join(data_dir, "obs.csv"))
      return data
  
imports: import logging
  from functools import reduce
  from operator import add
  from os.path import dirname, join
  import arviz
  import numpy
  import pandas
  import pymc
  import pytest
  from formulae import design_matrices
  import bambi
  from bambi.terms import CommonTerm, GroupSpecificTerm
label_desc: Use image node_id 4 for calling a global function with example usage: init_data() and returns: data