code: def setUp(self):
      super().setUp()
      self._encode = encoder._TensorFlowPngEncoder()
      self._rgb = (
          np.arange(12 * 34 * 3).reshape((12, 34, 3)).astype(np.uint8)
      )
      self._rgba = (
          np.arange(21 * 43 * 4).reshape((21, 43, 4)).astype(np.uint8)
      )
  
file_path: tensorboard/tensorboard/util/encoder_test.py
imports: import numpy
  import tensorflow
  from tensorboard.util import encoder
label_desc: Use image node_id 1 for calling the TensorFlowPngEncoderTest obj's underlying member method code with example usage: obj.setUp() without return types