code: def test_log_only_strings_as_keys(mock_run):
      run = mock_run()
      with pytest.raises(ValueError):
          run.log({1: 1000})
      with pytest.raises(ValueError):
          run.log({("tup", "idx"): 1000})
  
imports: import pytest
  import wandb
label_desc: Use image node_id 4 for calling a global function with example usage: test_log_only_strings_as_keys(mock_run) without return types