code: def test_dtype_from_str():
      assert feature.dtype_from_str("int64") == np.int64
      assert feature.dtype_from_str("uint8") == np.uint8
  
imports: import numpy
  import pytest
  import tensorflow
  from tensorflow_datasets.core.features import feature
  from tensorflow_datasets.core.features import image_feature
  from tensorflow_datasets.core.proto import feature_pb2
label_desc: Use image node_id 10 for calling a global function with example usage: test_dtype_from_str() without return types