code: def _serialize_normalized_array(array, fmt='png', quality=70):
    
    dtype = array.dtype
    assert np.issubdtype(dtype, np.unsignedinteger)
    assert np.max(array) <= np.iinfo(dtype).max
    assert array.shape[-1] > 1  # array dims must have been squeezed
  
    image = PIL.Image.fromarray(array)
    image_bytes = BytesIO()
    image.save(image_bytes, fmt, quality=quality)
    # TODO: Python 3 could save a copy here by using `getbuffer()` instead.
    image_data = image_bytes.getvalue()
    return image_data
docs: Given a normalized array, returns byte representation of image encoding.
  
    Args:
      array: NumPy array of dtype uint8 and range 0 to 255
      fmt: string describing desired file format, defaults to 'png'
      quality: specifies compression quality from 0 to 100 for lossy formats
  
    Returns:
      image data as BytesIO buffer