code: def ds():
      dataset = hl.balding_nichols_model(1, 100, 100)
      dataset = dataset.key_cols_by(s=hl.str(dataset.sample_idx + 1))
      return dataset
  
file_path: hail/hail/python/test/hail/methods/relatedness/test_identity_by_descent.py
imports: import os
  import pytest
  import subprocess
  import unittest
  import hail
  import hail.utils
  from ...helpers import test_timeout, qobtest
label_desc: Use image node_id 1 for calling a global function with example usage: ds() and returns: dataset