code: def read_image(path):
      with tf.gfile.GFile(path, "rb") as f:
          image = f.read()
      return image
  
file_path: luminoth/luminoth/utils/dataset.py
imports: import tensorflow
  from lxml import etree
label_desc: Use image node_id 3 for calling a global function with example usage: read_image(path) and returns: image