title: mAP graph during training doesn't show
body: <p>I use this command to train in colab</p>
  
  <pre><code>!./darknet detector train data/obj.data cfg/yolov3_custom.cfg darknet53.conv.74 -dont_show -map
  </code></pre>
  
  <p>and when I click on chart.png
  all I see is this it doesn't show mAP
  <a href="https://i.stack.imgur.com/aStOY.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/aStOY.png" alt="enter image description here"></a></p>