code: def test_validate_fail():
      _ = validate_data_format_str("weird_string")
  
file_path: kapre/tests/test_backend.py
imports: import pytest
  import numpy
  import librosa
  import tensorflow
  from tensorflow.keras import backend
  from kapre import backend
  from kapre.backend import magnitude_to_decibel, validate_data_format_str
  from utils import SRC
label_desc: Use image node_id 7 for calling a global function with example usage: test_validate_fail() without return types