class_docstr: Recreate a different inference graph to accept images encoded as png. 
class_docstr_tok: ["Recreate","a","different","inference","graph","to","accept","images","encoded","as","png","."]
code: def inputs(self):
      # The inference graph only accepts a single image, which is different to the training model.
      return [tf.TensorSpec((None,), tf.string, "input_img_bytes")]
  
imports: import argparse
  import cv2
  from tensorpack import tfv1
  from tensorpack import *
  from tensorpack.tfutils.export import ModelExporter
label_desc: Use image node_id 1 for calling the InferenceOnlyModel obj's underlying member method code with example usage: obj.inputs() and returns: list