code: def img_encode(arr, **kwargs):
      
      sio = BytesIO()
      imsave(sio, arr, **kwargs)
      sio.seek(0)
      img_format = kwargs['format'] if kwargs.get('format') else 'png'
      img_str = base64.b64encode(sio.getvalue()).decode()
  
      return 'data:image/{};base64,{}'.format(img_format, img_str)
docs: Encode ndarray to base64 string image data
      
      Parameters
      ----------
      arr: ndarray (rows, cols, depth)
      kwargs: passed directly to matplotlib.image.imsave