title: What does "--logtostderr" mean in the command line while using tensorflow's object detection api?
body: <p>when training object detection models using tensorflow, we always input</p>
  
  <pre><code>python train.py --logtostderr --train_dir=training/ --pipeline_config_path=training/ssd_mobilenet_v1_pets.config
  </code></pre>
  
  <p>But I wonder what the functionality of "--logtostderr" is ? what if omit it?</p>